2024

  • D. J. Strauss, F. I. Corona-Strauss, A. Mai, and S. A. Hillyard, “Fifty Years After: The N1 Effect Travels Down to the Brainstem,” bioRxiv, 2024. doi:10.1101/2024.02.23.581747
    [BibTeX] [Abstract] [Download PDF]
    Fifty years ago, it was reported that selective attention affects the N1 wave in auditory event-related potentials. We revisited the original study design but integrated the state of the art knowledge on short auditory stimuli and neural signal processing. In particular, one series of tone bursts has been replaced by chirp stimuli which are optimized to evoke consistent brainstem potentials at low and medium stimulation levels. Auditory selective attention affected the chirp-evoked response in subcortical structures, even at level of the inferior colliculi. A single-trial time-frequency analysis of the full-range (0-250ms) event-related potentials showed that selective attention increases the spectrotemporal consistency across trials in the corticofugal auditory pathway, at least from the N1 wave down to the auditory brainstem response.Competing Interest StatementThe authors have declared no competing interest.
    @Article{straea2024,
      author       = {Daniel J. Strauss and Farah I. Corona-Strauss and Adrian Mai and Steven A. Hillyard},
      journal      = {bioRxiv},
      title        = {Fifty Years After: The N1 Effect Travels Down to the Brainstem},
      year         = {2024},
      abstract     = {Fifty years ago, it was reported that selective attention affects the N1 wave in auditory event-related potentials. We revisited the original study design but integrated the state of the art knowledge on short auditory stimuli and neural signal processing. In particular, one series of tone bursts has been replaced by chirp stimuli which are optimized to evoke consistent brainstem potentials at low and medium stimulation levels. Auditory selective attention affected the chirp-evoked response in subcortical structures, even at level of the inferior colliculi. A single-trial time-frequency analysis of the full-range (0-250ms) event-related potentials showed that selective attention increases the spectrotemporal consistency across trials in the corticofugal auditory pathway, at least from the N1 wave down to the auditory brainstem response.Competing Interest StatementThe authors have declared no competing interest.},
      doi          = {10.1101/2024.02.23.581747},
      elocation-id = {2024.02.23.581747},
      eprint       = {https://www.biorxiv.org/content/early/2024/02/28/2024.02.23.581747.full.pdf},
      publisher    = {Cold Spring Harbor Laboratory},
      url          = {https://www.biorxiv.org/content/early/2024/02/28/2024.02.23.581747},
    }

2023

  • D. J. Strauss, A. L. Francis, J. Vibell, and F. I. Corona-Strauss, “The Role of Attention in Immersion: The Two-Competitor Model,” bioRxiv (revised version in press, Brain Research Bulletin), 2023. doi:10.1101/2023.07.10.548435
    [BibTeX] [Abstract] [Download PDF]
    Currently, we face an exponentially increasing interest in immersion, especially sensory-driven immersion, mainly due to the rapid development of ideas and business models centered around a digital virtual universe as well as the increasing availability of affordable immersive technologies for education, communication, and entertainment. However, a clear definition of \textquoterightimmersion\textquoteright, in terms of established neurocognitive concepts and measurable properties, remains elusive, slowing research on the human side of immersive interfaces. To address this problem, we propose a conceptual, taxonomic model of attention in immersion. We argue (a) modeling immersion theoretically as well as studying immersion experimentally requires a detailed characterization of the role of attention in immersion, even though (b) attention, while necessary, cannot be a sufficient condition for defining immersion. Our broader goal is to characterize immersion in terms that will be compatible with established psychophysiolgical measures that could then in principle be used for the assessment and eventually the optimization of an immersive experience. We start from the perspective that immersion requires the projection of attention to an induced reality, and build on accepted taxonomies of different modes of attention for the development of our two-competitor model. The two–competitor model allows for a quantitative implementation and has an easy graphical interpretation. It helps to highlight the important link between different modes of attention and affect in studying immersion.Competing Interest StatementThe authors have declared no competing interest.
    @Article{straea2023,
      author       = {Daniel J. Strauss and Alexander L. Francis and Jonas Vibell and Farah I. Corona-Strauss},
      journal      = {bioRxiv (revised version in press, Brain Research Bulletin)},
      title        = {The Role of Attention in Immersion: The Two-Competitor Model},
      year         = {2023},
      abstract     = {Currently, we face an exponentially increasing interest in immersion, especially sensory-driven immersion, mainly due to the rapid development of ideas and business models centered around a digital virtual universe as well as the increasing availability of affordable immersive technologies for education, communication, and entertainment. However, a clear definition of {\textquoteright}immersion{\textquoteright}, in terms of established neurocognitive concepts and measurable properties, remains elusive, slowing research on the human side of immersive interfaces. To address this problem, we propose a conceptual, taxonomic model of attention in immersion. We argue (a) modeling immersion theoretically as well as studying immersion experimentally requires a detailed characterization of the role of attention in immersion, even though (b) attention, while necessary, cannot be a sufficient condition for defining immersion. Our broader goal is to characterize immersion in terms that will be compatible with established psychophysiolgical measures that could then in principle be used for the assessment and eventually the optimization of an immersive experience. We start from the perspective that immersion requires the projection of attention to an induced reality, and build on accepted taxonomies of different modes of attention for the development of our two-competitor model. The two--competitor model allows for a quantitative implementation and has an easy graphical interpretation. It helps to highlight the important link between different modes of attention and affect in studying immersion.Competing Interest StatementThe authors have declared no competing interest.},
      doi          = {10.1101/2023.07.10.548435},
      elocation-id = {2023.07.10.548435},
      eprint       = {https://www.biorxiv.org/content/early/2023/07/11/2023.07.10.548435.full.pdf},
      publisher    = {Cold Spring Harbor Laboratory},
      url          = {https://www.biorxiv.org/content/early/2023/07/11/2023.07.10.548435},
    }
  • A. Mai, S. A. Hillyard, and D. J. Strauss, “Linear modeling of brain activity during selective attention to continuous speech: the critical role of the N1 effect in event-related potentials to acoustic edges,” bioRxiv, 2023. doi:10.1101/2023.07.14.548994
    [BibTeX] [Abstract] [Download PDF]
    Recent work in the field of neural speech tracking provided evidence for a cortical representation of speech through superposition of event-related responses to acoustic edges, an idea closely related to the popular linear modeling approach to study cortical synchronization to speech via magneto- or electroencephalography (M/EEG). However, it is still unclear to what extent speech-evoked event-related potentials (ERPs) including well-established phenomena, e.g., the N1 selective attention effect, contribute to the regression-based analyses. Here, we addressed this question by analyzing an EEG dataset obtained during a simple multispeaker selective attention task in which participants were cued to attend to only one of two competing speakers. Segmenting the ongoing EEG based on acoustic edges, we were able to replicate previous findings of event-related responses to speech in MEG data with particularly clear P1-N1-P2 complexes. Crucially, speech-evoked ERPs exhibited significant effects of attention in line with the auditory N1 effect. Comparing speech-evoked ERPs to the linear regression results revealed two major findings. First, temporal response functions (TRFs) obtained from forward modeling were strongly temporally as well as spatially correlated with corresponding true ERPs. Second, effects of attention demonstrated by the stimulus reconstruction (SR) accuracies obtained from backward modeling appeared to be driven by a consistent generation of speech-evoked ERPs including the N1 effect. Taken together, our observations reveal a direct link between ERPs to acoustic edges in speech and the linear TRF and SR modeling techniques. We emphasize the enhancement in signal-to-noise ratio provided by repeatedly evoked N1 responses to be a critical factor in facilitating the tracking and subsequent higher-order processing of selectively attended speech. In addition to that, the findings imply a cortical speech representation through superimposed speech-evoked ERPs in accordance with recent arguments promoting the neural evoked-response speech tracking model.Competing Interest StatementThe authors have declared no competing interest.
    @Article{maiea2023a,
      author       = {Adrian Mai and Steven A. Hillyard and Daniel J. Strauss},
      journal      = {bioRxiv},
      title        = {Linear modeling of brain activity during selective attention to continuous speech: the critical role of the N1 effect in event-related potentials to acoustic edges},
      year         = {2023},
      abstract     = {Recent work in the field of neural speech tracking provided evidence for a cortical representation of speech through superposition of event-related responses to acoustic edges, an idea closely related to the popular linear modeling approach to study cortical synchronization to speech via magneto- or electroencephalography (M/EEG). However, it is still unclear to what extent speech-evoked event-related potentials (ERPs) including well-established phenomena, e.g., the N1 selective attention effect, contribute to the regression-based analyses. Here, we addressed this question by analyzing an EEG dataset obtained during a simple multispeaker selective attention task in which participants were cued to attend to only one of two competing speakers. Segmenting the ongoing EEG based on acoustic edges, we were able to replicate previous findings of event-related responses to speech in MEG data with particularly clear P1-N1-P2 complexes. Crucially, speech-evoked ERPs exhibited significant effects of attention in line with the auditory N1 effect. Comparing speech-evoked ERPs to the linear regression results revealed two major findings. First, temporal response functions (TRFs) obtained from forward modeling were strongly temporally as well as spatially correlated with corresponding true ERPs. Second, effects of attention demonstrated by the stimulus reconstruction (SR) accuracies obtained from backward modeling appeared to be driven by a consistent generation of speech-evoked ERPs including the N1 effect. Taken together, our observations reveal a direct link between ERPs to acoustic edges in speech and the linear TRF and SR modeling techniques. We emphasize the enhancement in signal-to-noise ratio provided by repeatedly evoked N1 responses to be a critical factor in facilitating the tracking and subsequent higher-order processing of selectively attended speech. In addition to that, the findings imply a cortical speech representation through superimposed speech-evoked ERPs in accordance with recent arguments promoting the neural evoked-response speech tracking model.Competing Interest StatementThe authors have declared no competing interest.},
      doi          = {10.1101/2023.07.14.548994},
      elocation-id = {2023.07.14.548994},
      eprint       = {https://www.biorxiv.org/content/early/2023/07/16/2023.07.14.548994.full.pdf},
      publisher    = {Cold Spring Harbor Laboratory},
      url          = {https://www.biorxiv.org/content/early/2023/07/16/2023.07.14.548994},
    }
  • A. Schroeer, F. I. Corona-Strauss, R. Hannemann, S. A. Hackley, and D. J. Strauss, “Electromyographic Correlates of Effortful Listening in the Vestigial Auriculomotor System,” bioRxiv, 2023. doi:10.1101/2023.07.19.549747
    [BibTeX] [Abstract] [Download PDF]
    Recently, electromyographic (EMG) signals of auricular muscles have been shown to be an indicator of spatial auditory attention in humans, based on a vestigial pinna-orienting system. Because spatial auditory attention in a competing speaker task is closely related to the more gen-eralized concept of attentional effort in listening, the current study inves-tigated the possibility that the EMG activity of auricular muscles could also reflect correlates of effortful listening in general. Twenty subjects were recruited. EMG signals from the left and right superior and poste-rior auricular muscles (SAM, PAM) were recorded while subjects attended a target podcast in a competing speaker paradigm. Three different lev-els of listening effort, low, medium, and high, were generated by varying the number and pitch of distractor streams, as well as the signal-to-noise ratio. All audio streams were either presented from a loudspeaker placed in front of the participants (0\textdegree), or in the back (180\textdegree). Averaged PAM activity was not affected by different levels of listening effort, but was sig-nificantly larger when stimuli were presented from the back, as opposed to the front. Averaged SAM activity, however, was significantly larger in the high listening effort condition, compared to low and medium, but was not affected by stimulus direction. We hypothesize that the increased SAM activity is a response of the vestigial pinna\textendashorienting system to effortful stream segregation task.Competing Interest StatementThe authors have declared no competing interest.
    @Article{schroeerea2023a,
      author       = {Andreas Schroeer and Farah I. Corona-Strauss and Ronny Hannemann and Steven A. Hackley and Daniel J. Strauss},
      journal      = {bioRxiv},
      title        = {Electromyographic Correlates of Effortful Listening in the Vestigial Auriculomotor System},
      year         = {2023},
      abstract     = {Recently, electromyographic (EMG) signals of auricular muscles have been shown to be an indicator of spatial auditory attention in humans, based on a vestigial pinna-orienting system. Because spatial auditory attention in a competing speaker task is closely related to the more gen-eralized concept of attentional effort in listening, the current study inves-tigated the possibility that the EMG activity of auricular muscles could also reflect correlates of effortful listening in general. Twenty subjects were recruited. EMG signals from the left and right superior and poste-rior auricular muscles (SAM, PAM) were recorded while subjects attended a target podcast in a competing speaker paradigm. Three different lev-els of listening effort, low, medium, and high, were generated by varying the number and pitch of distractor streams, as well as the signal-to-noise ratio. All audio streams were either presented from a loudspeaker placed in front of the participants (0{\textdegree}), or in the back (180{\textdegree}). Averaged PAM activity was not affected by different levels of listening effort, but was sig-nificantly larger when stimuli were presented from the back, as opposed to the front. Averaged SAM activity, however, was significantly larger in the high listening effort condition, compared to low and medium, but was not affected by stimulus direction. We hypothesize that the increased SAM activity is a response of the vestigial pinna{\textendash}orienting system to effortful stream segregation task.Competing Interest StatementThe authors have declared no competing interest.},
      doi          = {10.1101/2023.07.19.549747},
      elocation-id = {2023.07.19.549747},
      eprint       = {https://www.biorxiv.org/content/early/2023/07/21/2023.07.19.549747.full.pdf},
      publisher    = {Cold Spring Harbor Laboratory},
      url          = {https://www.biorxiv.org/content/early/2023/07/21/2023.07.19.549747},
    }
  • D. Thinnes, M. W. Laschke, M. D. Menger, J. F. Vibell, and D. J. Strauss, “Cross-Modal Attention Assistance in Digital Operating Theaters: An Electroencephalography Assessment of Multimodal Priming,” IEEE EMBS NER, 2023.
    [BibTeX]
    @article{thinnesea2023,
      author  = {David Thinnes and Matthias W. Laschke and Michael D. Menger and Jonas F. Vibell and Daniel J. Strauss},
      journal = {IEEE EMBS NER},
      title   = {Cross-Modal Attention Assistance in Digital Operating Theaters: An Electroencephalography Assessment of Multimodal Priming},
      year    = {2023},
    }
  • B. Buchheit, E. N. Schneider, C. Lehser, and D. J. Strauss, “Foreshadowing Maneuvers transmitted by a Tactile System affecting Motion Sickness,” IEEE EMBS NER, 2023.
    [BibTeX]
    @article{buchea2023a,
      author  = {Benedikt Buchheit and Elena N. Schneider and Caroline Lehser and Daniel J. Strauss},
      journal = {IEEE EMBS NER},
      title   = {Foreshadowing Maneuvers transmitted by a Tactile System affecting Motion Sickness},
      year    = {2023},
    }
  • B. Buchheit, T. Grün, E. N. Schneider, M. Alayan, and D. J. Strauss, “Motion Sickness Prediction Based on Passenger’s Self Evaluation,” IEEE Conference on Intelligent Transportation Systems, 2023.
    [BibTeX]
    @article{buchea2023b,
      author  = {Benedikt Buchheit and Tobias Grün and Elena N. Schneider and Mohamad Alayan and Daniel J. Strauss},
      journal = {IEEE Conference on Intelligent Transportation Systems},
      title   = {Motion Sickness Prediction Based on Passenger’s Self Evaluation},
      year    = {2023},
    }
  • E. N. Schneider, B. Buchheit, M. Alayan, and D. J. Strauss, “Decreased Electrodermal Responses to Driving Maneuvers Using an Active Chassis System,” Annu Int Conf IEEE Eng Med Biol Soc, 2023.
    [BibTeX]
    @article{schneiderea2023,
      author  = {Elena N. Schneider and Benedikt Buchheit and Mohamad Alayan and Daniel J. Strauss},
      journal = {Annu Int Conf IEEE Eng Med Biol Soc},
      title   = {Decreased Electrodermal Responses to Driving Maneuvers Using an Active Chassis System},
      year    = {2023},
    }
  • L. Renz, M. Serman, S. Best, N. S. Jensen, C. Wilson, J. Foellmer, A. Schroeer, D. J. Strauss, and F. I. Corona-Strauss, “Dynamic range compression directionality affects effortful listening in complex listening situations for hearing aid users,” Annu Int Conf IEEE Eng Med Biol Soc, 2023.
    [BibTeX]
    @article{renzea2023,
      author  = {Laura Renz and Maja Serman and Sebastian Best and Niels S. Jensen and Cecil Wilson and Jurek Foellmer and Andreas Schroeer and Daniel J. Strauss and Farah I. Corona-Strauss},
      journal = {Annu Int Conf IEEE Eng Med Biol Soc},
      title   = {Dynamic range compression directionality affects effortful listening in complex listening situations for hearing aid users},
      year    = {2023},
    }
  • T. Biloborodova, B. Brosnan, I. Skarga-Bandurova, and D. J. Strauss, “Generalization Ability in Medical ImageAnalysis with Small-Scale Imbalanced Datasets: Insights from Neural Network Learning Progress in Artificial Intelligence,” EPIA , Lecture Notes in Computer Science., 2023.
    [BibTeX]
    @article{bilioborodovaea2023,
      author  = {Biloborodova, T. and Brosnan, B. and Skarga-Bandurova, I. and Strauss, D.J.},
      journal = {EPIA , Lecture Notes in Computer Science.},
      title   = {Generalization Ability in Medical ImageAnalysis with Small-Scale Imbalanced Datasets: Insights from Neural Network Learning Progress in Artificial Intelligence},
      year    = {2023},
    }
  • A. Mai, M. Serman, S. Best, N. S. Jensen, C. Wilson, J. Foellmer, A. Schroeer, D. J. Strauss, and F. I. Corona-Strauss, “Adapting In- and Out-Field-Of-View Processing in Hearing Aids Diminishes Listening Effort Indexed by EEG Phase Organization,” IEEE EMBS Conf. NER, 2023.
    [BibTeX]
    @article{maiea2023b,
      author  = {Adrian Mai and Maja Serman and Sebastian Best and Niels S. Jensen and Cecil Wilson and Jurek Foellmer and Andreas Schroeer and Daniel J. Strauss and Farah I. Corona-Strauss},
      journal = {IEEE EMBS Conf. NER},
      title   = {Adapting In- and Out-Field-Of-View Processing in Hearing Aids Diminishes Listening Effort Indexed by EEG Phase Organization},
      year    = {2023},
    }
  • A. Mai, M. Serman, S. Best, N. S. Jensen, C. Wilson, J. Foellmer, A. Schroeer, D. J. Strauss, and F. I. Corona-Strauss, “Tuning of In- and Out-Field-Of-View Processing in Hearing Aids Benefits Global Speech Tracking in Hearing-Impaired Listeners,” IEEE EMBC, 2023.
    [BibTeX]
    @article{maiea2023c,
      author  = {Adrian Mai and Maja Serman and Sebastian Best and Niels S. Jensen and Cecil Wilson and Jurek Foellmer and Andreas Schroeer and Daniel J. Strauss and Farah I. Corona-Strauss},
      journal = {IEEE EMBC},
      title   = {Tuning of In- and Out-Field-Of-View Processing in Hearing Aids Benefits Global Speech Tracking in Hearing-Impaired Listeners},
      year    = {2023},
    }
  • A. Schroeer, M. R. Andersen, M. L. Rank, R. Hannemann, E. B. Petersen, F. M. Rønne, D. J. Strauss, and F. I. Corona-Strauss, “Assessment of Vestigial Auriculomotor Activity to Acoustic Stimuli Using Electrodes In and Around the Ear,” Trends in Hearing, vol. 27, 2023. doi:10.1177/23312165231200158
    [BibTeX]
    @Article{schroeerea2023b,
      author    = {Schroeer, Andreas and Andersen, Martin Rune and Rank, Mike Lind and Hannemann, Ronny and Petersen, Eline Borch and Rønne, Filip Marchman and Strauss, Daniel J. and Corona-Strauss, Farah I.},
      journal   = {Trends in Hearing},
      title     = {Assessment of Vestigial Auriculomotor Activity to Acoustic Stimuli Using Electrodes In and Around the Ear},
      year      = {2023},
      issn      = {2331-2165},
      month     = jan,
      volume    = {27},
      doi       = {10.1177/23312165231200158},
      publisher = {SAGE Publications},
    }
  • P. Flotho, C. Heiss, G. Steidl, and D. J. Strauss, “Lagrangian motion magnification with double sparse optical flow decomposition,” Frontiers in Applied Mathematics and Statistics, vol. 9, 2023. doi:10.3389/fams.2023.1164491
    [BibTeX]
    @Article{flotea2023,
      author    = {Flotho, Philipp and Heiss, Cosmas and Steidl, Gabriele and Strauss, Daniel J.},
      journal   = {Frontiers in Applied Mathematics and Statistics},
      title     = {Lagrangian motion magnification with double sparse optical flow decomposition},
      year      = {2023},
      issn      = {2297-4687},
      month     = sep,
      volume    = {9},
      doi       = {10.3389/fams.2023.1164491},
      publisher = {Frontiers Media SA},
    }

2022

  • P. Flotho, S. Nomura, B. Kuhn, and D. J. Strauss, “Software for Non-Parametric Image Registration of 2-Photon Imaging Data,” Journal of Biophotonics, vol. 15, iss. 8, 2022. doi:10.1002/jbio.202100330
    [BibTeX] [Abstract]
    Functional 2-photon microscopy is a key technology for imaging neuronal activity. The recorded image sequences, however, can contain non-rigid movement artifacts which requires high-accuracy movement correction. Variational optical flow (OF) estimation is a group of methods for motion analysis with established performance in many computer vision areas. However, it has yet to be adapted to the statistics of 2-photon neuroimaging data. In this work, we present the motion compensation method Flow-Registration that outperforms previous alignment tools and allows to align and reconstruct even low signal-to-noise ratio 2-photon imaging data and is able to compensate high-divergence displacements during local drug injections. The method is based on statistics of such data and integrates previous advances in variational OF estimation. Our method is available as an easy-to-use ImageJ/FIJI plugin as well as a MATLAB toolbox with modular, object oriented file IO, native multi-channel support and compatibility with existing 2-photon imaging suites.
    @Article{flotea2022a,
      author    = {Flotho, P. and Nomura, S. and Kuhn, B. and Strauss, D. J.},
      journal   = {Journal of Biophotonics},
      title     = {Software for Non-Parametric Image Registration of 2-Photon Imaging Data},
      year      = {2022},
      month     = {may},
      number    = {8},
      volume    = {15},
      abstract  = {Functional 2-photon microscopy is a key technology for imaging neuronal activity. The recorded image sequences, however, can contain non-rigid movement artifacts which requires high-accuracy movement correction. Variational optical flow (OF) estimation is a group of methods for motion analysis with established performance in many computer vision areas. However, it has yet to be adapted to the statistics of 2-photon neuroimaging data. In this work, we present the motion compensation method Flow-Registration that outperforms previous alignment tools and allows to align and reconstruct even low signal-to-noise ratio 2-photon imaging data and is able to compensate high-divergence displacements during local drug injections. The method is based on statistics of such data and integrates previous advances in variational OF estimation. Our method is available as an easy-to-use ImageJ/FIJI plugin as well as a MATLAB toolbox with modular, object oriented file IO, native multi-channel support and compatibility with existing 2-photon imaging suites.},
      doi       = {10.1002/jbio.202100330},
      keywords  = {ImageJ/FIJI plugin,MATLAB toolbox,confocal microscopy,image registration,movement correction,optical flow,optical imaging,two-photon microscopy},
      publisher = {Wiley},
    }
  • D. Chang, D. Thinnes, P. Au, D. Maziero, V. Stenger, S. Sinnett, and J. Vibell, “Sound-modulations of visual motion perception implicates the cortico-vestibular brain,” NeuroImage, 2022. doi:10.1016/j.neuroimage.2022.119285
    [BibTeX]
    @Article{changea2022,
      author  = {Chang, D. and Thinnes, D. and Au, P. and Maziero, D. and Stenger, V. and Sinnett, S. and Vibell, J.},
      journal = {NeuroImage},
      title   = {Sound-modulations of visual motion perception implicates the cortico-vestibular brain},
      year    = {2022},
      month   = {05},
      doi     = {10.1016/j.neuroimage.2022.119285},
    }
  • P. Flotho, C. Heiss, G. Steidl, and D. J. Strauss, “Lagrangian Motion Magnification with Double Sparse Optical Flow Decomposition,” arXiv, 2022. doi:10.48550/ARXIV.2204.07636
    [BibTeX] [Abstract] [Download PDF]
    Motion magnification techniques aim at amplifying and hence revealing subtle motion in videos. There are basically two main approaches to reach this goal, namely via Eulerian or Lagrangian techniques. While the first one magnifies motion implicitly by operating directly on image pixels, the Lagrangian approach uses optical flow techniques to extract and amplify pixel trajectories. Microexpressions are fast and spatially small facial expressions that are difficult to detect. In this paper, we propose a novel approach for local Lagrangian motion magnification of facial micromovements. Our contribution is three-fold: first, we fine-tune the recurrent all-pairs field transforms for optical flows (RAFT) deep learning approach for faces by adding ground truth obtained from the variational dense inverse search (DIS) for optical flow algorithm applied to the CASME II video set of faces. This enables us to produce optical flows of facial videos in an efficient and sufficiently accurate way. Second, since facial micromovements are both local in space and time, we propose to approximate the optical flow field by sparse components both in space and time leading to a double sparse decomposition. Third, we use this decomposition to magnify micro-motions in specific areas of the face, where we introduce a new forward warping strategy using a triangular splitting of the image grid and barycentric interpolation of the RGB vectors at the corners of the transformed triangles. We demonstrate the very good performance of our approach by various examples.
    @Article{flotea2022c,
      author    = {Flotho, P. and Heiss, C. and Steidl, G. and Strauss, D. J.},
      journal   = {arXiv},
      title     = {Lagrangian Motion Magnification with Double Sparse Optical Flow Decomposition},
      year      = {2022},
      abstract  = {Motion magnification techniques aim at amplifying and hence revealing subtle motion in videos. There are basically two main approaches to reach this goal, namely via Eulerian or Lagrangian techniques. While the first one magnifies motion implicitly by operating directly on image pixels, the Lagrangian approach uses optical flow techniques to extract and amplify pixel trajectories. Microexpressions are fast and spatially small facial expressions that are difficult to detect. In this paper, we propose a novel approach for local Lagrangian motion magnification of facial micromovements. Our contribution is three-fold: first, we fine-tune the recurrent all-pairs field transforms for optical flows (RAFT) deep learning approach for faces by adding ground truth obtained from the variational dense inverse search (DIS) for optical flow algorithm applied to the CASME II video set of faces. This enables us to produce optical flows of facial videos in an efficient and sufficiently accurate way. Second, since facial micromovements are both local in space and time, we propose to approximate the optical flow field by sparse components both in space and time leading to a double sparse decomposition. Third, we use this decomposition to magnify micro-motions in specific areas of the face, where we introduce a new forward warping strategy using a triangular splitting of the image grid and barycentric interpolation of the RGB vectors at the corners of the transformed triangles. We demonstrate the very good performance of our approach by various examples.},
      copyright = {Creative Commons Zero v1.0 Universal},
      doi       = {10.48550/ARXIV.2204.07636},
      eprint    = {2204.07636},
      keywords  = {Computer Vision and Pattern Recognition (cs.CV), FOS: Computer and information sciences, FOS: Computer and information sciences},
      publisher = {arXiv},
      url       = {https://www.snnu.uni-saarland.de/dsd_momag/},
    }
  • P. Flotho, C. Heiss, G. Steidl, and D. J. Strauss, “Lagrangian Motion Magnification with Landmark-Prior and Sparse PCA for Facial Microexpressions and Micromovements,” in 2022 44th Annual International Conference of the IEEE Engineering in Medicine &amp Biology Society (EMBC), 2022. doi:10.1109/embc48229.2022.9871549
    [BibTeX] [Abstract]
    Video motion magnification methods are motion visualization techniques that aim to magnify subtle and imper-ceptibly small motions in videos. They fall into two main groups where Eulerian methods work on the pixel grid with implicit motion information and Lagrangian methods use explicitly estimated motion and modify point trajectories. The motion in high framerate videos of faces can contain a wide variety of information that ranges from microexpressions over pulse or respiratory rate to cues on speech and affective state. In his work, we propose a novel strategy for Lagrangian motion magnification that integrates landmark information from the face as well as an approach to decompose facial motions in an unsupervised manner using sparse PCA. We decompose the estimated displacements into different movement components that are subsequently amplified selectively. We propose two approaches: A landmark-based decomposition into global and local movements and a decomposition into multiple coherent motion components based on sparse PCA. Optical flow estimation is performed using a state-of-the-art deep learning-based method that we retrain on a microexpression database. Clinical relevance- This method could be applied to the annotation and analysis of micromovements for neurocognitive assessment and even novel, medical applications where micro-motions of the face might play a role.
    @InProceedings{flotea2022b,
      author    = {Flotho, P. and Heiss, C. and Steidl, G. and Strauss, D.J.},
      booktitle = {2022 44th Annual International Conference of the {IEEE} Engineering in Medicine {\&}amp Biology Society ({EMBC})},
      title     = {Lagrangian Motion Magnification with Landmark-Prior and Sparse {PCA} for Facial Microexpressions and Micromovements},
      year      = {2022},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {Video motion magnification methods are motion visualization techniques that aim to magnify subtle and imper-ceptibly small motions in videos. They fall into two main groups where Eulerian methods work on the pixel grid with implicit motion information and Lagrangian methods use explicitly estimated motion and modify point trajectories. The motion in high framerate videos of faces can contain a wide variety of information that ranges from microexpressions over pulse or respiratory rate to cues on speech and affective state. In his work, we propose a novel strategy for Lagrangian motion magnification that integrates landmark information from the face as well as an approach to decompose facial motions in an unsupervised manner using sparse PCA. We decompose the estimated displacements into different movement components that are subsequently amplified selectively. We propose two approaches: A landmark-based decomposition into global and local movements and a decomposition into multiple coherent motion components based on sparse PCA. Optical flow estimation is performed using a state-of-the-art deep learning-based method that we retrain on a microexpression database. Clinical relevance- This method could be applied to the annotation and analysis of micromovements for neurocognitive assessment and even novel, medical applications where micro-motions of the face might play a role.},
      doi       = {10.1109/embc48229.2022.9871549},
      keywords  = {microexpressions,motion analysis,motion magnification,motion visualization},
    }
  • B. Buchheit, E. N. Schneider, M. Alayan, and D. J. Strauss, “Motion Sickness related Route Profiling for Evaluation of the Sensory Conlict in Real-Driving Studies (accepted),” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @inproceedings{flotea2022b,
      author = {Buchheit, B. and Schneider, E. N. and Alayan, M. and Strauss, D.J.},
      title = {Motion Sickness related Route Profiling for Evaluation of the Sensory Conlict in Real-Driving Studies (accepted)},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      year = {2022}
    }
  • A. Mai, M. Serman, S. Best, N. Jensen, J. Foellmer, A. Schroeer, C. Welsch, D. J. Strauss, and F. Corona-Strauss, “Speech Tracking in Complex Auditory Scenes with Differentiated In- and Out-Field-Of-View Processing in Hearing Aids (accepted),” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @inproceedings{flotea2022b,
      author = {Mai, A. and Serman, M. and Best, S. and Jensen, N. and Foellmer, J. and Schroeer, A. and Welsch, C. and Strauss, D.J. and Corona-Strauss, F.},
      title = {Speech Tracking in Complex Auditory Scenes with Differentiated In- and Out-Field-Of-View Processing in Hearing Aids (accepted)},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      year = {2022}
    }
  • D. Thinnes, S. A. Hillyard, F. I. Corona-Strauss, J. F. Vibell, and D. J. Strauss, “Preliminary Outcomes of Cross-Modal Pre-Cuing in a Visual Discrimination Task,” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @InProceedings{thinnesea2022,
      author    = {Thinnes, D. and Hillyard, S. A. and Corona-Strauss, F. I. and Vibell, J. F. and Strauss, D. J.},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      title     = {Preliminary Outcomes of Cross-Modal Pre-Cuing in a Visual Discrimination Task},
      year      = {2022},
    }
  • S. K. Pandey, D. J. Strauss, and P. Flotho, “Impact of Medical Face Masks on Facial Alignment Performance,” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @InProceedings{pandea2022a,
      author    = {Pandey, S. K. and Strauss, D. J. and Flotho, P.},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      title     = {Impact of Medical Face Masks on Facial Alignment Performance},
      year      = {2022},
    }
  • P. Flotho, M. J. Bhamborae, C. Karls, M. Lehser, and D. J. Strauss, “Comparing Video Compression for Archiving Camera-based Physiological Measurements for rPPG and Motion Analysis,” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @InProceedings{flotea2022c,
      author    = {Flotho, P. and Bhamborae, M. J. and Karls, C. and Lehser, M. and Strauss, D. J.},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      title     = {Comparing Video Compression for Archiving Camera-based Physiological Measurements for rPPG and Motion Analysis},
      year      = {2022},
    }
  • A. Wilhelm, P. J. Schäfer, P. Flotho, F. I. Corona-Strauss, and D. J. Strauss, “Auditory attention decoding of ongoing EEG without acoustic stimuli using a 3D convolutional neural network in a four-speaker acoustic environment,” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @InProceedings{wilh2022a,
      author    = {Wilhelm, A. and Schäfer, P. J. and Flotho, P. and Corona-Strauss, F. I. and Strauss, D. J.},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      title     = {Auditory attention decoding of ongoing EEG without acoustic stimuli using a 3D convolutional neural network in a four-speaker acoustic environment},
      year      = {2022},
    }
  • A. Schroeer, M. R. Andersen, M. L. Rank, R. Hannemann, E. B. Petersen, F. M. Rønne, D. J. Strauss, and F. I. Corona-Strauss, “Classifying the Direction of Auditory Stimuli by Dry-Contact Ear-EMG,” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @InProceedings{Schrea2022a,
      author    = {Schroeer, A. and Andersen, M. R. and Rank, M. L. and Hannemann, R. and Petersen, E. B. and Rønne, F. M. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      title     = {Classifying the Direction of Auditory Stimuli by Dry-Contact Ear-EMG},
      year      = {2022},
    }
  • E. N. Schneider, B. Buchheit, and D. J. Strauss, “Regional Variations of Electrodermal Activity in a Motion Sickness Paradigm,” in Annu Int Conf IEEE Eng Med Biol Soc, 2022.
    [BibTeX]
    @InProceedings{Schnea2022a,
      author    = {Schneider, E. N. and Buchheit, B. and Strauss, D. J.},
      booktitle = {Annu Int Conf IEEE Eng Med Biol Soc},
      title     = {Regional Variations of Electrodermal Activity in a Motion Sickness Paradigm},
      year      = {2022},
    }

2021

  • P. Flotho, M. J. Bhamborae, T. Grün, C. Trenado, D. Thinnes, D. Limbach, and D. J. Strauss, “Multimodal Data Acquisition at SARS-CoV-2 Drive Through Screening Centers: Setup Description and Experiences in Saarland, Germany,” Journal of Biophotonics, vol. 14, iss. 8, p. e202000512, 2021. doi:10.1002/jbio.202000512
    [BibTeX] [Abstract]
    SARS-CoV-2 drive through screening centers (DTSC) have been implemented worldwide as a fast and secure way of mass screening. We use DTSCs as a platform for the acquisition of multimodal datasets that are needed for the development of remote screening methods. Our acquisition setup consists of an array of thermal, infrared and RGB cameras as well as microphones and we apply methods from computer vision and computer audition for the contactless estimation of physiological parameters. We have recorded a multimodal dataset of DTSC participants in Germany for the development of remote screening methods and symptom identification. Acquisition in the early stages of a pandemic and in regions with high infection rates can facilitate and speed up the identification of infection specific symptoms and large-scale data acquisition at DTSC is possible without disturbing the flow of operation.
    @Article{flotea2021b,
      author    = {Flotho, P. and Bhamborae, M.J. and Grün, T. and Trenado, C. and Thinnes, D. and Limbach, D. and Strauss, D. J.},
      journal   = {Journal of Biophotonics},
      title     = {Multimodal Data Acquisition at SARS-CoV-2 Drive Through Screening Centers: Setup Description and Experiences in Saarland, Germany},
      year      = {2021},
      month     = {jun},
      number    = {8},
      pages     = {e202000512},
      volume    = {14},
      abstract  = {SARS-CoV-2 drive through screening centers (DTSC) have been implemented worldwide as a fast and secure way of mass screening. We use DTSCs as a platform for the acquisition of multimodal datasets that are needed for the development of remote screening methods. Our acquisition setup consists of an array of thermal, infrared and RGB cameras as well as microphones and we apply methods from computer vision and computer audition for the contactless estimation of physiological parameters. We have recorded a multimodal dataset of DTSC participants in Germany for the development of remote screening methods and symptom identification. Acquisition in the early stages of a pandemic and in regions with high infection rates can facilitate and speed up the identification of infection specific symptoms and large-scale data acquisition at DTSC is possible without disturbing the flow of operation.},
      doi       = {10.1002/jbio.202000512},
      keywords  = {COVID-19,SARS-CoV-2,computer vision,drive through screening,non-contact medical assessment},
      publisher = {Wiley},
    }
  • A. Schroeer, F. I. Corona-Strauss, O. Ozdamar, J. Jorge Bohorquez, and D. J. Strauss, “Speech induced binaural beats: Electrophysiological assessment of binaural interaction,” The Journal of the Acoustical Society of America, vol. 149, iss. 2, pp. 788-799, 2021. doi:10.1121/10.0003442
    [BibTeX] [Abstract]
    This paper introduces and evaluates a speech signal manipulation scheme that generates transient speech induced binaural beats (SBBs). These SBBs can only be perceived when different signals are presented dichotically (to both ears). Event-related potentials were recorded in 22 normal-hearing subjects. Dichotic stimulus presentation reliably evoked auditory late responses (ALRs) in all subjects using such manipulated signals. As control measurements, diotic stimulation modalities were presented to confirm that the ALRs were not evoked by the speech signal itself or that the signal manipulation scheme created audible artifacts. Since diotic measurements evoked no ALRs, responses from dichotic stimulation are a pure correlate of binaural interaction. While there are several auditory stimuli (mostly modulated sinusoids or noise) that share this characteristic, none of them are based on running speech. Because SBBs can be added to any arbitrary speech signal, they could easily be combined with psychoacoustic tests, for example speech reception thresholds, adding an objective measure of binaural interaction.
    @Article{schrea2021a,
      author    = {Schroeer, A. and Corona-Strauss, F. I. and Ozdamar, O. and Jorge Bohorquez, J. and Strauss, D. J.},
      journal   = {The Journal of the Acoustical Society of America},
      title     = {Speech induced binaural beats: Electrophysiological assessment of binaural interaction},
      year      = {2021},
      month     = {feb},
      number    = {2},
      pages     = {788--799},
      volume    = {149},
      abstract  = {This paper introduces and evaluates a speech signal manipulation scheme that generates transient speech induced binaural beats (SBBs). These SBBs can only be perceived when different signals are presented dichotically (to both ears). Event-related potentials were recorded in 22 normal-hearing subjects. Dichotic stimulus presentation reliably evoked auditory late responses (ALRs) in all subjects using such manipulated signals. As control measurements, diotic stimulation modalities were presented to confirm that the ALRs were not evoked by the speech signal itself or that the signal manipulation scheme created audible artifacts. Since diotic measurements evoked no ALRs, responses from dichotic stimulation are a pure correlate of binaural interaction. While there are several auditory stimuli (mostly modulated sinusoids or noise) that share this characteristic, none of them are based on running speech. Because SBBs can be added to any arbitrary speech signal, they could easily be combined with psychoacoustic tests, for example speech reception thresholds, adding an objective measure of binaural interaction.},
      doi       = {10.1121/10.0003442},
      publisher = {Acoustical Society of America ({ASA})},
    }
  • B. Buchheit, E. N. Schneider, M. Alayan, F. Dauth, and D. J. Strauss, “Motion Sickness Prediction in Self-Driving Cars Using the 6DOF-SVC Model,” IEEE Transactions on Intelligent Transportation Systems, vol. 23, iss. 8, pp. 13582-13591, 2021. doi:10.1109/tits.2021.3125802
    [BibTeX] [Abstract]
    Drivers who assign the driving task to a self-driving car switch to a passive role to work or enjoy leisure time like a traditional passenger. Consequently, the risk of developing motion sickness (MS) symptoms increases significantly. Adapting one’s own driving behavior, e.g. by choosing an alternative route or decreasing the velocity, offers future intelligent vehicles a way to independently prevent MS. Accurate predictions help to improve journey’s planning of the vehicle and make correct decisions so as to minimize disruption to the traffic flow. In the present study our contribution is as follow: We conduct two studies by focusing on real-world driving under self-driving conditions and induced MS symptoms in passengers. We simulated driving parameters of the conducted studies to extract simulated driving dynamics and contrasted them with recorded driving dynamics. A well-known model of MS, namely the six-degrees-of-freedom subjective vertical conflict model (6DOF-SVC model) was utilized to predict motion sickness incidence (MSI) for both studies. In order to do so, we implemented a customized Human-Vehicle-Model to map the car’s dynamics to the head, which is crucial to apply the 6DOF-SVC model. We evaluated different Human-Vehicle-Model conditions and optimized the parameters of the 6DOF-SVC model to increase prediction accuracy in the case of our experiments. Note that our modeling approach enabled capture effects of missing visual anticipation and cognitive distraction that we present in our experiment. It is concluded that the 6DOF-SVC model is applicable in realistic driving scenarios as the ones used in our study.
    @Article{buchea2021b,
      author    = {Buchheit, Benedikt and Schneider, Elena N and Alayan, Mohamad and Dauth, Florian and Strauss, Daniel J},
      journal   = {{IEEE} Transactions on Intelligent Transportation Systems},
      title     = {Motion Sickness Prediction in Self-Driving Cars Using the 6DOF-{SVC} Model},
      year      = {2021},
      month     = {aug},
      number    = {8},
      pages     = {13582--13591},
      volume    = {23},
      abstract  = {Drivers who assign the driving task to a self-driving car switch to a passive role to work or enjoy leisure time like a traditional passenger. Consequently, the risk of developing motion sickness (MS) symptoms increases significantly. Adapting one's own driving behavior, e.g. by choosing an alternative route or decreasing the velocity, offers future intelligent vehicles a way to independently prevent MS. Accurate predictions help to improve journey's planning of the vehicle and make correct decisions so as to minimize disruption to the traffic flow. In the present study our contribution is as follow: We conduct two studies by focusing on real-world driving under self-driving conditions and induced MS symptoms in passengers. We simulated driving parameters of the conducted studies to extract simulated driving dynamics and contrasted them with recorded driving dynamics. A well-known model of MS, namely the six-degrees-of-freedom subjective vertical conflict model (6DOF-SVC model) was utilized to predict motion sickness incidence (MSI) for both studies. In order to do so, we implemented a customized Human-Vehicle-Model to map the car's dynamics to the head, which is crucial to apply the 6DOF-SVC model. We evaluated different Human-Vehicle-Model conditions and optimized the parameters of the 6DOF-SVC model to increase prediction accuracy in the case of our experiments. Note that our modeling approach enabled capture effects of missing visual anticipation and cognitive distraction that we present in our experiment. It is concluded that the 6DOF-SVC model is applicable in realistic driving scenarios as the ones used in our study.},
      doi       = {10.1109/tits.2021.3125802},
      keywords  = {Autonomous vehicles,Human factors,Intelligent vehicle,Modeling and simulation,Motion sickness},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • P. Flotho, D. Thinnes, B. Kuhn, C. J. Roome, J. F. Vibell, and D. J. Strauss, “Fast variational alignment of non-flat 1D displacements for applications in neuroimaging,” Journal of Neuroscience Methods, vol. 353, p. 109076, 2021. doi:10.1016/j.jneumeth.2021.109076
    [BibTeX] [Abstract] [Download PDF]
    Background: In the context of signal analysis and pattern matching, alignment of 1D signals for the comparison of signal morphologies is an important problem. For image processing and computer vision, 2D optical flow (OF) methods find wide application for motion analysis and image registration and variational OF methods have been continuously improved over the past decades. New method: We propose a variational method for the alignment and displacement estimation of 1D signals. We pose the estimation of non-flat displacements as an optimization problem with a similarity and smoothness term similar to variational OF estimation. To this end, we can make use of efficient optimization strategies that allow real-time applications on consumer grade hardware. Results: We apply our method to two applications from functional neuroimaging: The alignment of 2-photon imaging line scan recordings and the denoising of evoked and event-related potentials in single trial matrices. We can report state of the art results in terms of alignment quality and computing speeds. Existing methods: Existing methods for 1D alignment target mostly constant displacements, do not allow native subsample precision or precise control over regularization or are slower than the proposed method. Conclusions: Our method is implemented as a MATLAB toolbox and is online available. It is suitable for 1D alignment problems, where high accuracy and high speed is needed and non-constant displacements occur.
    @Article{flotea2021,
      author    = {Flotho, Philipp and Thinnes, David and Kuhn, Bernd and Roome, Christopher J and Vibell, Jonas F and Strauss, Daniel J},
      journal   = {Journal of Neuroscience Methods},
      title     = {Fast variational alignment of non-flat 1D displacements for applications in neuroimaging},
      year      = {2021},
      issn      = {0165-0270},
      month     = {apr},
      pages     = {109076},
      volume    = {353},
      abstract  = {Background: In the context of signal analysis and pattern matching, alignment of 1D signals for the comparison of signal morphologies is an important problem. For image processing and computer vision, 2D optical flow (OF) methods find wide application for motion analysis and image registration and variational OF methods have been continuously improved over the past decades. New method: We propose a variational method for the alignment and displacement estimation of 1D signals. We pose the estimation of non-flat displacements as an optimization problem with a similarity and smoothness term similar to variational OF estimation. To this end, we can make use of efficient optimization strategies that allow real-time applications on consumer grade hardware. Results: We apply our method to two applications from functional neuroimaging: The alignment of 2-photon imaging line scan recordings and the denoising of evoked and event-related potentials in single trial matrices. We can report state of the art results in terms of alignment quality and computing speeds. Existing methods: Existing methods for 1D alignment target mostly constant displacements, do not allow native subsample precision or precise control over regularization or are slower than the proposed method. Conclusions: Our method is implemented as a MATLAB toolbox and is online available. It is suitable for 1D alignment problems, where high accuracy and high speed is needed and non-constant displacements occur.},
      doi       = {10.1016/j.jneumeth.2021.109076},
      keywords  = {1D alignment,1D displacement,Confocal microscopy,Event related potentials,Evoked potentials,Line scan,Two-photon microscopy,Variational methods},
      publisher = {Elsevier {BV}},
      url       = {https://www.sciencedirect.com/science/article/pii/S016502702100011X},
    }
  • B. Buchheit, E. S. Schneider, M. Alayan, F. Dauth, and D. J. Strauss, “Methodological standardization of electrodermal activity to validate subjective assessments of motion sickness,” in Neural Engineering (NER), 10th International IEEE EMBS Conference on, 2021.
    [BibTeX]
    @InProceedings{buchea2021a,
      author    = {Buchheit, B. and Schneider, E. S. and Alayan, M. and Dauth, F. and Strauss, D. J.},
      booktitle = {Neural Engineering (NER), 10th International IEEE EMBS Conference on},
      title     = {Methodological standardization of electrodermal activity to validate subjective assessments of motion sickness},
      year      = {2021},
    }

2020

  • D. J. Strauss, F. I. Corona-Strauss, A. Schroeer, P. Flotho, R. Hannemann, and S. A. Hackley, “Vestigial auriculomotor activity indicates the direction of auditory attention in humans,” eLife, vol. 9, p. e54536, 2020. doi:10.7554/elife.54536
    [BibTeX] [Abstract]
    Unlike dogs and cats, people do not point their ears as they focus attention on novel, salient, or task-relevant stimuli. Our species may nevertheless have retained a vestigial pinna-orienting system that has persisted as a ‘neural fossil’ within in the brain for about 25 million years. Consistent with this hypothesis, we demonstrate that the direction of auditory attention is reflected in sustained electrical activity of muscles within the vestigial auriculomotor system. Surface electromyograms (EMGs) were taken from muscles that either move the pinna or alter its shape. To assess reflexive, stimulus-driven attention we presented novel sounds from speakers at four different lateral locations while the participants silently read a boring text in front of them. To test voluntary, goal-directed attention we instructed participants to listen to a short story coming from one of these speakers, while ignoring a competing story from the corresponding speaker on the opposite side. In both experiments, EMG recordings showed larger activity at the ear on the side of the attended stimulus, but with slightly different patterns. Upward movement (perking) differed according to the lateral focus of attention only during voluntary orienting; rearward folding of the pinna’s upper-lateral edge exhibited such differences only during reflexive orienting. The existence of a pinna-orienting system in humans, one that is experimentally accessible, offers opportunities for basic as well as applied science.
    @Article{straea2020,
      author    = {Strauss, D.J. and Corona-Strauss, F.I. and Schroeer, A. and Flotho, P. and Hannemann, R. and Hackley, S.A.},
      journal   = {{eLife}},
      title     = {Vestigial auriculomotor activity indicates the direction of auditory attention in humans},
      year      = {2020},
      month     = {jul},
      pages     = {e54536},
      volume    = {9},
      abstract  = {Unlike dogs and cats, people do not point their ears as they focus attention on novel, salient, or task-relevant stimuli. Our species may nevertheless have retained a vestigial pinna-orienting system that has persisted as a 'neural fossil' within in the brain for about 25 million years. Consistent with this hypothesis, we demonstrate that the direction of auditory attention is reflected in sustained electrical activity of muscles within the vestigial auriculomotor system. Surface electromyograms (EMGs) were taken from muscles that either move the pinna or alter its shape. To assess reflexive, stimulus-driven attention we presented novel sounds from speakers at four different lateral locations while the participants silently read a boring text in front of them. To test voluntary, goal-directed attention we instructed participants to listen to a short story coming from one of these speakers, while ignoring a competing story from the corresponding speaker on the opposite side. In both experiments, EMG recordings showed larger activity at the ear on the side of the attended stimulus, but with slightly different patterns. Upward movement (perking) differed according to the lateral focus of attention only during voluntary orienting; rearward folding of the pinna's upper-lateral edge exhibited such differences only during reflexive orienting. The existence of a pinna-orienting system in humans, one that is experimentally accessible, offers opportunities for basic as well as applied science.},
      doi       = {10.7554/elife.54536},
      publisher = {{eLife} Sciences Publications, Ltd},
    }
  • M. J. Bhamborae, P. Flotho, A. Mai, E. N. Schneider, A. L. Francis, and D. J. Strauss, “Towards Contactless Estimation of Electrodermal Activity Correlates,” in 2020 42nd Annual International Conference of the IEEE Engineering in Medicine & Biology Society (EMBC), 2020. doi:10.1109/embc44109.2020.9176359
    [BibTeX] [Abstract]
    This paper presents a proof-of-concept for contactless and nonintrusive estimation of electrodermal activity (EDA) correlates using a camera. RGB video of the palm under three different lighting conditions showed that for a suitably chosen illumination strategy the data from the camera is sufficient to estimate EDA correlates which agree with the measurements done using laboratory grade physiological sensors. The effects we see in the recorded video can be attributed to sweat gland activity, which inturn is known to be correlated with EDA. These effects are so pronounced that simple pixel statistics can be used to quantify them. Such a method benefits from advances in computer vision and graphics research and has the potential to be used in affective computing and psychophysiology research where contact based sensors may not be suitable.
    @InProceedings{bhamea2020,
      author    = {Bhamborae, M.J. and Flotho, P. and Mai, A. and Schneider, E.N. and Francis, A.L. and Strauss, D.J.},
      booktitle = {2020 42nd Annual International Conference of the {IEEE} Engineering in Medicine {\&} Biology Society ({EMBC})},
      title     = {Towards Contactless Estimation of Electrodermal Activity Correlates},
      year      = {2020},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {This paper presents a proof-of-concept for contactless and nonintrusive estimation of electrodermal activity (EDA) correlates using a camera. RGB video of the palm under three different lighting conditions showed that for a suitably chosen illumination strategy the data from the camera is sufficient to estimate EDA correlates which agree with the measurements done using laboratory grade physiological sensors. The effects we see in the recorded video can be attributed to sweat gland activity, which inturn is known to be correlated with EDA. These effects are so pronounced that simple pixel statistics can be used to quantify them. Such a method benefits from advances in computer vision and graphics research and has the potential to be used in affective computing and psychophysiology research where contact based sensors may not be suitable.},
      doi       = {10.1109/embc44109.2020.9176359},
      keywords  = {affective computing,camera-based,electrodermal activity,non-intrusive,remote psychophysiology},
    }
  • M. J. Bhamborae, P. Flotho, A. Mai, E. N. Schneider, A. L. Francis, and D. J. Strauss, “Functional Skin Imaging: Towards Contactless Estimation of Electrodermal Activity Correlates,” in Psychophysiology, 2020, p. S35–S35.
    [BibTeX]
    @inproceedings{bhamea2020b,
      title={Functional Skin Imaging: Towards Contactless Estimation of Electrodermal Activity Correlates},
      author={Bhamborae, M.J. and Flotho, P. and Mai, A. and Schneider, E.N. and Francis, A.L. and Strauss, D.J.},
      booktitle={Psychophysiology},
      volume={57},
      pages={S35--S35},
      year={2020},
      organization={WILEY 111 RIVER ST, HOBOKEN 07030-5774, NJ USA}
    }
  • L. Haab, P. Flotho, D. Eckert, K. Schwerdtfeger, M. Hülser, D. J. Strauss, and M. Möller, “Time-Multiplexed Illumination for simultaneous Structural and Functional Voltage Sensitive Dye Recordings with a single Photo Sensor,” in 2020 42nd Annual International Conference of the IEEE Engineering in Medicine &amp Biology Society (EMBC), 2020. doi:10.1109/embc44109.2020.9176694
    [BibTeX] [Abstract]
    The in-vivo optical imaging of the cortical surface provides the ability to record different types of biophysiological signals, e.g., structural information, intrinsic signals, like blood oxygenation coupled reflection changes as well as extrinsic properties of voltage sensitive probes, like fluorescent voltage-sensitive dyes. The recorded data sets have very high temporal and spatial resolutions on a meso- to macroscopic scale, which surpass conventional multi-electrode recordings. Both, intrinsic and functional data sets, each provide unique information about temporal and spatial dynamics of cortical functioning, yet have individual drawbacks. To optimize the informational value it would thus be opportune to combine different types of optical imaging in a near simultaneous recording.Due to the low signal-to-noise ratio of voltage-sensitive dyes it is necessary to reduce stray light pollution below the level of the camera’s dark noise. It is thus impossible to record full-spectrum optical data sets. We address this problem by a time-multiplexed illumination, bespoke to the utilized voltage sensitive dye, to record an alternating series of intrinsic and extrinsic frames by a high-frequency CMOS sensor. These near simultaneous data series can be used to compare the mutual influence of intrinsic and extrinsic dynamics (with regards to extracorporeal functional imaging) as well as for motion compensation and thus for minimizing frame averaging, which in turn results in increased spatial precision of functional data and in a reduction of necessary experimental data sets (3R principle).
    @InProceedings{haabea2020,
      author    = {Haab, L. and Flotho, P. and Eckert, D. and Schwerdtfeger, K. and H\"{u}lser, M. and Strauss, D.J. and M\"{o}ller, M.},
      booktitle = {2020 42nd Annual International Conference of the {IEEE} Engineering in Medicine {\&}amp Biology Society ({EMBC})},
      title     = {Time-Multiplexed Illumination for simultaneous Structural and Functional Voltage Sensitive Dye Recordings with a single Photo Sensor},
      year      = {2020},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {The in-vivo optical imaging of the cortical surface provides the ability to record different types of biophysiological signals, e.g., structural information, intrinsic signals, like blood oxygenation coupled reflection changes as well as extrinsic properties of voltage sensitive probes, like fluorescent voltage-sensitive dyes. The recorded data sets have very high temporal and spatial resolutions on a meso- to macroscopic scale, which surpass conventional multi-electrode recordings. Both, intrinsic and functional data sets, each provide unique information about temporal and spatial dynamics of cortical functioning, yet have individual drawbacks. To optimize the informational value it would thus be opportune to combine different types of optical imaging in a near simultaneous recording.Due to the low signal-to-noise ratio of voltage-sensitive dyes it is necessary to reduce stray light pollution below the level of the camera's dark noise. It is thus impossible to record full-spectrum optical data sets. We address this problem by a time-multiplexed illumination, bespoke to the utilized voltage sensitive dye, to record an alternating series of intrinsic and extrinsic frames by a high-frequency CMOS sensor. These near simultaneous data series can be used to compare the mutual influence of intrinsic and extrinsic dynamics (with regards to extracorporeal functional imaging) as well as for motion compensation and thus for minimizing frame averaging, which in turn results in increased spatial precision of functional data and in a reduction of necessary experimental data sets (3R principle).},
      doi       = {10.1109/embc44109.2020.9176694},
      keywords  = {Image Registration,Optical Imaging,time-multiplexed illumination,voltage sensitive dye imaging},
    }
  • Z. Schäfer, L. Haab, D. J. Strauss, K. Takahashi, and K. Schwerdtfeger, “Detection of information flow between cortical laminae activities and auditory evoked potentials in rats by means of Granger causality,” in 2020 42nd Annual International Conference of the IEEE Engineering in Medicine &amp Biology Society (EMBC), 2020. doi:10.1109/embc44109.2020.9176719
    [BibTeX] [Abstract]
    We seek to understand the relation between invasive high-resolution data and non-invasive measurement in an animal model in an auditory sensory adaptation experimental setting. In a previous study, we estimated the mutual information between the phase of auditory evoked responses (AER) with the phase of local field potentials (LFP) of auditory cortices at different frequency ranges. The results showed a consistently high level of information sharing between the AER activities as well as the responses from the granular layer, which was known as the main thalamo-recipient layer. However, mutual information was fundamentally an undirected measure of information flow. In this study we investigated how well we could characterize direction of information flow, by using Granger causality (GC), between different cortical laminae and functional projections on to the AER activities. We obtained that based on the GC coefficients, we are able to extract the connectivity between different cortical laminae to some extend and also a strong connection between the AER and granular layer. In our future study, we would like to construct a reliable picture of network connectivity, both functionally and anatomically, between different layers at more specified frequencies and much finer temporal resolutions.
    @InProceedings{schaea2020,
      author    = {Sch\"{a}fer, Z. and Haab, L. and Strauss, D.J. and Takahashi, K. and Schwerdtfeger, K.},
      booktitle = {2020 42nd Annual International Conference of the {IEEE} Engineering in Medicine {\&}amp Biology Society ({EMBC})},
      title     = {Detection of information flow between cortical laminae activities and auditory evoked potentials in rats by means of Granger causality},
      year      = {2020},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {We seek to understand the relation between invasive high-resolution data and non-invasive measurement in an animal model in an auditory sensory adaptation experimental setting. In a previous study, we estimated the mutual information between the phase of auditory evoked responses (AER) with the phase of local field potentials (LFP) of auditory cortices at different frequency ranges. The results showed a consistently high level of information sharing between the AER activities as well as the responses from the granular layer, which was known as the main thalamo-recipient layer. However, mutual information was fundamentally an undirected measure of information flow. In this study we investigated how well we could characterize direction of information flow, by using Granger causality (GC), between different cortical laminae and functional projections on to the AER activities. We obtained that based on the GC coefficients, we are able to extract the connectivity between different cortical laminae to some extend and also a strong connection between the AER and granular layer. In our future study, we would like to construct a reliable picture of network connectivity, both functionally and anatomically, between different layers at more specified frequencies and much finer temporal resolutions.},
      doi       = {10.1109/embc44109.2020.9176719},
    }

2019

  • L. Haab, C. Lehser, F. I. Corona-Strauss, C. Bernarding, H. Seidler, R. Hannemann, and D. J. Strauss, “Implementation and Long-Term Evaluation of a Hearing Aid Supported Tinnitus Treatment Using Notched Environmental Sounds,” IEEE Journal of Translational Engineering in Health and Medicine, vol. 7, pp. 1-9, 2019. doi:10.1109/jtehm.2019.2897570
    [BibTeX] [Abstract]
    Recent work has shown that sharp spectral edges in acoustic stimuli might have advantageous effects in the treatment of tonal tinnitus. In the course of this paper, we evaluate the long-term effects of spectrally notched hearing aids on the subjective tinnitus distress. By merging recent experimental work with a computational tinnitus model, we modified the commercially available behind-the-ear hearing aids so that a frequency band of 0.5 octaves, centered on the patient’s individual tinnitus frequency, was blocked out. Those hearing aids employ a steep notch filter that filters environmental sounds to suppress the tinnitus-related changes in neural firing by lateral inhibition. The computational model reveals a renormalization of pathologically increased neural response reliability and synchrony in response to spectrally modified input. The target group, fitted with spectrally notched hearing aids, was matched with a comparable control group, fitted with standard hearing aids of the same type but without a notch filter. We analyze the subjective self-assessment by tinnitus questionnaires, and we monitor the objective distress correlates in auditory evoked response phase data. Both, subjective and objective results show a noticeable trend of a larger therapeutic benefit for notched hearing correction.
    @Article{haabea2019,
      author    = {Haab, L. and Lehser, C. and Corona-Strauss, F. I. and Bernarding, C. and Seidler, H. and Hannemann, R. and Strauss, D. J.},
      journal   = {{IEEE} Journal of Translational Engineering in Health and Medicine},
      title     = {Implementation and Long-Term Evaluation of a Hearing Aid Supported Tinnitus Treatment Using Notched Environmental Sounds},
      year      = {2019},
      pages     = {1-9},
      volume    = {7},
      abstract  = {Recent work has shown that sharp spectral edges in acoustic stimuli might have advantageous effects in the treatment of tonal tinnitus. In the course of this paper, we evaluate the long-term effects of spectrally notched hearing aids on the subjective tinnitus distress. By merging recent experimental work with a computational tinnitus model, we modified the commercially available behind-the-ear hearing aids so that a frequency band of 0.5 octaves, centered on the patient's individual tinnitus frequency, was blocked out. Those hearing aids employ a steep notch filter that filters environmental sounds to suppress the tinnitus-related changes in neural firing by lateral inhibition. The computational model reveals a renormalization of pathologically increased neural response reliability and synchrony in response to spectrally modified input. The target group, fitted with spectrally notched hearing aids, was matched with a comparable control group, fitted with standard hearing aids of the same type but without a notch filter. We analyze the subjective self-assessment by tinnitus questionnaires, and we monitor the objective distress correlates in auditory evoked response phase data. Both, subjective and objective results show a noticeable trend of a larger therapeutic benefit for notched hearing correction.},
      doi       = {10.1109/jtehm.2019.2897570},
      keywords  = {Tinnitus,clinical trial,hearing AIDS,notched acoustic stimulation,translational engineering},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • M. C. Kohl, E. Schebsdat, E. N. Schneider, A. Niehl, D. J. Strauss, Ö. Özdamar, and J. Bohórquez, “Fast acquisition of full-range auditory event-related potentials using an interleaved deconvolution approach,” The Journal of the Acoustical Society of America, vol. 145, iss. 1, p. 540, 2019. doi:10.1121/1.5087825
    [BibTeX] [Abstract]
    This work relates to recent advances in the field of auditory event-related potentials (ERP), specifically deconvolution-based ERP acquisition and single-trial processing. An efficient stimulus sequence optimization method for ERP deconvolution is proposed, achieving consistent noise attenuation within a broad designated frequency range. Furthermore, a stimulus presentation paradigm for the fast, interleaved acquisition of auditory brainstem, middle-latency and late responses featuring alternating periods of high-rate deconvolution sequences, and subsequent low-rate stimulation is investigated in 20 normal hearing subjects. Deconvolved sequence responses containing early and middle-latency ERP components are fused with subsequent late responses using a time-frequency resolved weighted averaging method based on cross-trial regularity, yielding a uniform signal-to-noise ratio of the full-range auditory ERP across investigated timescales. Obtained average ERP waveforms exhibit morphologies consistent with both literature values and reference recordings acquired in 15 normal hearing subjects using a prior art approach to full-range auditory ERP acquisition, with all prominent waves being visible in the grand average waveforms. Results suggest the proposed interleaved stimulus presentation and associated ERP processing methodology to be suitable for the fast, reliable extraction of full-range auditory processing correlates in future ERP studies.
    @Article{kohlea2019,
      author    = {Kohl, M. C. and Schebsdat, E. and Schneider, E. N. and Niehl, A. and Strauss, D. J. and Özdamar, Ö. and Bohórquez, J.},
      journal   = {The Journal of the Acoustical Society of America},
      title     = {Fast acquisition of full-range auditory event-related potentials using an interleaved deconvolution approach},
      year      = {2019},
      month     = {jan},
      number    = {1},
      pages     = {540},
      volume    = {145},
      abstract  = {This work relates to recent advances in the field of auditory event-related potentials (ERP), specifically deconvolution-based ERP acquisition and single-trial processing. An efficient stimulus sequence optimization method for ERP deconvolution is proposed, achieving consistent noise attenuation within a broad designated frequency range. Furthermore, a stimulus presentation paradigm for the fast, interleaved acquisition of auditory brainstem, middle-latency and late responses featuring alternating periods of high-rate deconvolution sequences, and subsequent low-rate stimulation is investigated in 20 normal hearing subjects. Deconvolved sequence responses containing early and middle-latency ERP components are fused with subsequent late responses using a time-frequency resolved weighted averaging method based on cross-trial regularity, yielding a uniform signal-to-noise ratio of the full-range auditory ERP across investigated timescales. Obtained average ERP waveforms exhibit morphologies consistent with both literature values and reference recordings acquired in 15 normal hearing subjects using a prior art approach to full-range auditory ERP acquisition, with all prominent waves being visible in the grand average waveforms. Results suggest the proposed interleaved stimulus presentation and associated ERP processing methodology to be suitable for the fast, reliable extraction of full-range auditory processing correlates in future ERP studies.},
      doi       = {10.1121/1.5087825},
      publisher = {Acoustical Society of America ({ASA})},
    }
  • N. Özgün, R. Bennewitz, and D. J. Strauss, “Friction in Passive Tactile Perception Induces Phase Coherency in Late Somatosensory Single Trial Sequences,” IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 27, iss. 2, pp. 129-138, 2019. doi:10.1109/tnsre.2019.2891915
    [BibTeX] [Abstract]
    — Event related potentials represent a noninvasive means for studying sensory and cognitive processes that occur in response to particular stimuli. Here, we report on a phase measure for estimating single trial interaction of late somatosensory potentials (LSPs) following a tribological well defined mechanical stimulation of the human fingertip. Stimuli are presented via a programmable Braille-display with actively switchable pins which was slid along the apex of the passive fingertip, i.e., the fingertip rested stationarily in a finger holding system with circular opening at the bottom. The event was the raising and the lowering of either one, three, or five lines of pins. Differences were identified by measures based on instantaneous phase synchronization to the stimuli across trials, in particular the wavelet phase synchronization stability (WPSS) measure for single trial sequences of LSPs. In particular, we show that the higher the friction the stronger and more localized the induced phase coherency is. We concluded that the WPSS analysis of single sequences of LSPs represents a reliable method which allows for the quantification of brain responses upon distinct tactile stimuli.
    @Article{ozgunea2019,
      author    = {{\"O}zg{\"u}n, N. and Bennewitz, R. and Strauss, D. J.},
      journal   = {{IEEE} Transactions on Neural Systems and Rehabilitation Engineering},
      title     = {Friction in Passive Tactile Perception Induces Phase Coherency in Late Somatosensory Single Trial Sequences},
      year      = {2019},
      month     = {feb},
      number    = {2},
      pages     = {129-138},
      volume    = {27},
      abstract  = {— Event related potentials represent a noninvasive means for studying sensory and cognitive processes that occur in response to particular stimuli. Here, we report on a phase measure for estimating single trial interaction of late somatosensory potentials (LSPs) following a tribological well defined mechanical stimulation of the human fingertip. Stimuli are presented via a programmable Braille-display with actively switchable pins which was slid along the apex of the passive fingertip, i.e., the fingertip rested stationarily in a finger holding system with circular opening at the bottom. The event was the raising and the lowering of either one, three, or five lines of pins. Differences were identified by measures based on instantaneous phase synchronization to the stimuli across trials, in particular the wavelet phase synchronization stability (WPSS) measure for single trial sequences of LSPs. In particular, we show that the higher the friction the stronger and more localized the induced phase coherency is. We concluded that the WPSS analysis of single sequences of LSPs represents a reliable method which allows for the quantification of brain responses upon distinct tactile stimuli.},
      doi       = {10.1109/tnsre.2019.2891915},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • E. Gonzalez-Trejo, H. Moegele, N. Pfleger, R. Hannemann, and D. J. Strauss, “Electroencephalographic Phase–Amplitude Coupling in Simulated Driving With Varying Modality-Specific Attentional Demand,” IEEE Trans Hum Mach Syst., vol. 49, iss. 6, pp. 589-598, 2019. doi:10.1109/thms.2019.2931011
    [BibTeX]
    @Article{kohlea2019,
      author  = {Gonzalez-Trejo, E. and Moegele, H. and Pfleger, N. and Hannemann, R. and Strauss, D. J.},
      journal = {IEEE Trans Hum Mach Syst.},
      title   = {Electroencephalographic Phase–Amplitude Coupling in Simulated Driving With Varying Modality-Specific Attentional Demand},
      year    = {2019},
      number  = {6},
      pages   = {589-598},
      volume  = {49},
      doi     = {10.1109/thms.2019.2931011},
    }
  • C. Bernarding, M. -C. Herbig, N. A. Pratapa, V. Choquet, J. Angermayer, and D. J. Strauss, “Time-Resolved In-Vehicle Drowsiness Monitoring Using Multimodal Electrophysiological Data,” in 2019 9th International IEEE/EMBS Conference on Neural Engineering (NER), 2019. doi:10.1109/ner.2019.8717182
    [BibTeX] [Abstract]
    Drowsiness of the driver is one of the major causes of car accidents. In the last years, the extraction of an objective drowsiness correlate to prevent drowsiness related accidents has gained more and more attention. The aim of the current study was the assessment of a time-resolved quantification of drowsiness correlates in multimodal psychophysiological data obtained during simulated driving. A further part of the study was the feasibility assessment of a drowsiness categorization by means of psychophysiological data. The heart rate, the heart rate variability, the skin conductance level and the relative band power ($\theta$, $\alpha$, $\beta$) as well as the $\alpha$/$\beta$ power ratio of the EEG were examined as objective correlates of drowsiness in 30 participants. The results show that, besides the skin conductance level, all investigated time-resolved psychophysiological measures showed the expected trends (ANOVA test, p < 0.01) described in the literature. The highest Pearson's correlation coefficient calculated between the subjective rating scale and objective index of drowsiness was noticeable for the time-resolved $\alpha$/$\beta$ power ratio in the parietal lobe. Thus, the drowsiness categorization was only realized for this index. The individual results show that this time-resolved psychophysiological index of drowsiness can reflect the participants' actual mental state. It is concluded, that the time-resolved $\alpha$/$\beta$ power ratio is a suitable objective index for drowsiness. Nevertheless, for a generalization of this measure a larger group of participants has to be investigated.
    @InProceedings{bernardingea2019,
      author    = {Bernarding, C. and Herbig, M.-C. and Pratapa, N. A. and Choquet, V. and Angermayer, J. and Strauss, D. J.},
      booktitle = {2019 9th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Time-Resolved In-Vehicle Drowsiness Monitoring Using Multimodal Electrophysiological Data},
      year      = {2019},
      month     = {mar},
      publisher = {{IEEE}},
      abstract  = {Drowsiness of the driver is one of the major causes of car accidents. In the last years, the extraction of an objective drowsiness correlate to prevent drowsiness related accidents has gained more and more attention. The aim of the current study was the assessment of a time-resolved quantification of drowsiness correlates in multimodal psychophysiological data obtained during simulated driving. A further part of the study was the feasibility assessment of a drowsiness categorization by means of psychophysiological data. The heart rate, the heart rate variability, the skin conductance level and the relative band power ($\theta$, $\alpha$, $\beta$) as well as the $\alpha$/$\beta$ power ratio of the EEG were examined as objective correlates of drowsiness in 30 participants. The results show that, besides the skin conductance level, all investigated time-resolved psychophysiological measures showed the expected trends (ANOVA test, p < 0.01) described in the literature. The highest Pearson's correlation coefficient calculated between the subjective rating scale and objective index of drowsiness was noticeable for the time-resolved $\alpha$/$\beta$ power ratio in the parietal lobe. Thus, the drowsiness categorization was only realized for this index. The individual results show that this time-resolved psychophysiological index of drowsiness can reflect the participants' actual mental state. It is concluded, that the time-resolved $\alpha$/$\beta$ power ratio is a suitable objective index for drowsiness. Nevertheless, for a generalization of this measure a larger group of participants has to be investigated.},
      doi       = {10.1109/ner.2019.8717182},
    }
  • B. Buchheit, F. Dauth, and D. J. Strauss, "Correlation Between the Electrodermal Activity and the Sensory Conflict Calculated by the 6 Degrees of Freedom - Subjective Vertical Conflict Model in a Real Driving Situation," in Neural Engineering (NER), 9th International IEEE EMBS Conference on, 2019.
    [BibTeX]
    @inproceedings{buchheitea2019,
      author = {Buchheit, B. and Dauth, F. and Strauss, D. J.},
      title = {Correlation Between the Electrodermal Activity and the Sensory Conflict Calculated by the 6 Degrees of Freedom - Subjective Vertical Conflict Model in a Real Driving Situation},
      booktitle = {Neural Engineering (NER), 9th International IEEE EMBS Conference on},
      year = {2019}
    }
  • P. Flotho, L. Haab, D. Eckert, K. Takahashi, K. Schwerdtfeger, and D. J. Strauss, "Semi-Synthetic Dataset for the Evaluation of Motion Compensation Approaches for Voltage Sensitive Dye Imaging," in 2019 9th International IEEE/EMBS Conference on Neural Engineering (NER), 2019. doi:10.1109/ner.2019.8716905
    [BibTeX] [Abstract]
    Intracranial, functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes) belongs to a group of invasive neuroimaging techniques with very high temporal and spatial resolutions on a meso-to macroscopic scale. Voltage sensitive dye imaging (VSDI) images brain activity with low temporal delays, but the raw signal has a poor signal to noise ratio.An important pre-processing step for many biomedical imaging techniques is image registration and motion compensation. We can apply motion compensation successfully for optical imaging of intrinsic signals but VSDI recordings have low spatial contrast and often do not contain fine grained texture details which are crucial for successful image based motion compensation. In this work, we design a semi-synthetic dataset based on real recordings and a dummy voltage sensitive dye response for the evaluation of advanced motion compensation strategies for VSDI. This dataset aims to be used as a benchmark for the development of novel motion compensation strategies for VSDI and to derive error bounds of the methodologies with respect to motion.
    @InProceedings{flothoea2019,
      author    = {Flotho, P. and Haab, L. and Eckert, D. and Takahashi, K. and Schwerdtfeger, K. and Strauss, D. J.},
      booktitle = {2019 9th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Semi-Synthetic Dataset for the Evaluation of Motion Compensation Approaches for Voltage Sensitive Dye Imaging},
      year      = {2019},
      month     = {mar},
      publisher = {{IEEE}},
      abstract  = {Intracranial, functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes) belongs to a group of invasive neuroimaging techniques with very high temporal and spatial resolutions on a meso-to macroscopic scale. Voltage sensitive dye imaging (VSDI) images brain activity with low temporal delays, but the raw signal has a poor signal to noise ratio.An important pre-processing step for many biomedical imaging techniques is image registration and motion compensation. We can apply motion compensation successfully for optical imaging of intrinsic signals but VSDI recordings have low spatial contrast and often do not contain fine grained texture details which are crucial for successful image based motion compensation. In this work, we design a semi-synthetic dataset based on real recordings and a dummy voltage sensitive dye response for the evaluation of advanced motion compensation strategies for VSDI. This dataset aims to be used as a benchmark for the development of novel motion compensation strategies for VSDI and to derive error bounds of the methodologies with respect to motion.},
      doi       = {10.1109/ner.2019.8716905},
      keywords  = {Image Registration,Motion Compensation,Optical Imaging,Semi-Synthetic Dataset,Temporal Modulation Imaging,VSDI},
    }
  • M. C. Kohl, E. Schebsdat, E. N. Schneider, and D. J. Strauss, "Denoising of Single-Trial Event-Related Potentials by Shrinkage and Phase Regularization of Analytic Wavelet Filterbank Coefficients (accepted)," in Neural Engineering (NER), 9th International IEEE EMBS Conference on, 2019.
    [BibTeX]
    @inproceedings{kohlea2019,
      author = {Kohl, M. C. and Schebsdat, E. and Schneider, E. N. and Strauss, D. J.},
      title = {Denoising of Single-Trial Event-Related Potentials by Shrinkage and Phase Regularization of Analytic Wavelet Filterbank Coefficients (accepted)},
      booktitle = {Neural Engineering (NER), 9th International IEEE EMBS Conference on},
      year = {2019}
    }
  • C. Lehser and D. J. Strauss, "Attentional Correlates in Somatosensory Potentials Evoked by Ultrasound Induced Virtual Objects in Mid-Air," in 2019 9th International IEEE/EMBS Conference on Neural Engineering (NER), 2019. doi:10.1109/ner.2019.8717129
    [BibTeX] [Abstract]
    The design of haptic feedback in human machine interfaces is an emerging field of research regarding the development of virtual and augmented reality. However, the perception and attentional processes of virtual haptic feedback, e.g., generated by focused ultrasound in mid-air, are only rarely investigated. This study evaluates attentional correlates in somatosensory evoked potentials (SEPs) elicited with ultrasonic stimuli in mid-air. Two stimulation tasks which differ in the level of difficulty are designed using different virtual shapes in mid-air. The SEPs are analyzed with the wavelet phase synchronization stability (WPSS). The results indicate a larger WPSS for the more difficult condition in the range of the P100 wave of the SEPs which could be a sign of larger attentional effort needed to solve the task.
    @InProceedings{lehserea2019,
      author    = {Lehser, C. and Strauss, D. J.},
      booktitle = {2019 9th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Attentional Correlates in Somatosensory Potentials Evoked by Ultrasound Induced Virtual Objects in Mid-Air},
      year      = {2019},
      month     = {mar},
      publisher = {{IEEE}},
      abstract  = {The design of haptic feedback in human machine interfaces is an emerging field of research regarding the development of virtual and augmented reality. However, the perception and attentional processes of virtual haptic feedback, e.g., generated by focused ultrasound in mid-air, are only rarely investigated. This study evaluates attentional correlates in somatosensory evoked potentials (SEPs) elicited with ultrasonic stimuli in mid-air. Two stimulation tasks which differ in the level of difficulty are designed using different virtual shapes in mid-air. The SEPs are analyzed with the wavelet phase synchronization stability (WPSS). The results indicate a larger WPSS for the more difficult condition in the range of the P100 wave of the SEPs which could be a sign of larger attentional effort needed to solve the task.},
      doi       = {10.1109/ner.2019.8717129},
      keywords  = {attention,haptics,human,interaction,machine,somatosen-,sory evoked potentials,ultrasound,wavelets},
    }
  • E. N. Schneider, C. Bernarding, A. Francis, B. W. Y. Hornsby, and D. J. Strauss, "A Quantitative Model of Listening Related Fatigue," in 2019 9th International IEEE/EMBS Conference on Neural Engineering (NER), 2019. doi:10.1109/ner.2019.8717046
    [BibTeX] [Abstract]
    Listening related fatigue is a common difficulty, especially for people with hearing loss. To reduce this negative impacts on their daily life, we have to understand the origins and the development of this fatigue. For this reason we developed a quantitative model of cognitive fatigue. We consider the development and course of fatigue, using a Simulink model including factors like internal and external demand, the discrepancy between expected and actual performance and the relation to reward. Besides, control and base motivation act as influencing factors on actual motivation. The functions changing according to the design of the fixed parameters are demanded effort, exerted effort, distress and fatigue. Fatigue acts as an additional input on motivation. Our focus lies mostly on listening-related fatigue. This type of fatigue occurs in difficult listening situations, especially in individuals with hearing loss. This model can be applied of a wide range of listening situations and provides a good basis for further research in this field.
    @InProceedings{schneiderea2019,
      author    = {Schneider, E. N. and Bernarding, C. and Francis, A. and Hornsby, B. W. Y. and Strauss, D. J.},
      booktitle = {2019 9th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {A Quantitative Model of Listening Related Fatigue},
      year      = {2019},
      month     = {mar},
      publisher = {{IEEE}},
      abstract  = {Listening related fatigue is a common difficulty, especially for people with hearing loss. To reduce this negative impacts on their daily life, we have to understand the origins and the development of this fatigue. For this reason we developed a quantitative model of cognitive fatigue. We consider the development and course of fatigue, using a Simulink model including factors like internal and external demand, the discrepancy between expected and actual performance and the relation to reward. Besides, control and base motivation act as influencing factors on actual motivation. The functions changing according to the design of the fixed parameters are demanded effort, exerted effort, distress and fatigue. Fatigue acts as an additional input on motivation. Our focus lies mostly on listening-related fatigue. This type of fatigue occurs in difficult listening situations, especially in individuals with hearing loss. This model can be applied of a wide range of listening situations and provides a good basis for further research in this field.},
      doi       = {10.1109/ner.2019.8717046},
    }

2018

  • P. J. Schaefer, F. I. Corona-Strauss, R. Hannemann, S. A. Hillyard, and D. J. Strauss, "Testing the Limits of the Stimulus Reconstruction Approach: Auditory Attention Decoding in a Four-Speaker Free Field Environment," Trends in Hearing, vol. 22, iss. 2331216518816600, p. 233121651881660, 2018. doi:10.1177/2331216518816600
    [BibTeX] [Abstract]
    Auditory attention can be defined as the cognitive process that enables us to selectively focus on relevant aspects of the acoustic environment while other aspects are ignored. The remarkable ability of the auditory system to focus on one out of several speakers in a multispeaker environment has become known as the cocktail party effect. Although the neural processes underlying selective auditory attention (SAA) are not well understood, it has recently been shown that the cortical representation of a listener's attended sound stream can be recorded noninvasively from the scalp and that stimulus reconstruction from single trial electroencephalographic (EEG) data enables the decoding of the orientation of auditory attention. The present study extends this approach by evaluating its efficacy in a naturalistic and challenging four-speaker acoustic free field environment, in which the four speakers were spatially separated and presented different but equally salient spoken messages to the listeners. Ten participants were instructed to focus SAA on a spoken prose message in one of the four loudspeakers while ignoring the remaining three streams of prose. Concurrent EEG activity recorded via 128 scalp channels was used for a stimulus reconstruction analysis. The results showed that this approach can be used to decode the orientation of SAA even in a complex and realistic acoustic setting. To confirm that the successful decoding was driven by correspondences between the recorded EEG activity and the attended speech envelopes, the analysis method was validated against randomly constructed sets of surrogate data and by correlations with behavioral data.
    @Article{schaeferea2018,
      author    = {Schaefer, P. J. and Corona-Strauss, F.I. and Hannemann, R. and Hillyard, S.A. and Strauss, D.J.},
      journal   = {Trends in Hearing},
      title     = {Testing the Limits of the Stimulus Reconstruction Approach: Auditory Attention Decoding in a Four-Speaker Free Field Environment},
      year      = {2018},
      month     = {jan},
      number    = {2331216518816600},
      pages     = {233121651881660},
      volume    = {22},
      abstract  = {Auditory attention can be defined as the cognitive process that enables us to selectively focus on relevant aspects of the acoustic environment while other aspects are ignored. The remarkable ability of the auditory system to focus on one out of several speakers in a multispeaker environment has become known as the cocktail party effect. Although the neural processes underlying selective auditory attention (SAA) are not well understood, it has recently been shown that the cortical representation of a listener's attended sound stream can be recorded noninvasively from the scalp and that stimulus reconstruction from single trial electroencephalographic (EEG) data enables the decoding of the orientation of auditory attention. The present study extends this approach by evaluating its efficacy in a naturalistic and challenging four-speaker acoustic free field environment, in which the four speakers were spatially separated and presented different but equally salient spoken messages to the listeners. Ten participants were instructed to focus SAA on a spoken prose message in one of the four loudspeakers while ignoring the remaining three streams of prose. Concurrent EEG activity recorded via 128 scalp channels was used for a stimulus reconstruction analysis. The results showed that this approach can be used to decode the orientation of SAA even in a complex and realistic acoustic setting. To confirm that the successful decoding was driven by correspondences between the recorded EEG activity and the attended speech envelopes, the analysis method was validated against randomly constructed sets of surrogate data and by correlations with behavioral data.},
      doi       = {10.1177/2331216518816600},
      keywords  = {auditory attention,cocktail party problem,electroencephalogram,selective attention,stimulus reconstruction},
      publisher = {{SAGE} Publications},
    }
  • Z. Mortezapouraghdam, F. I. Corona-Strauss, T. Takahashi, and D. J. Strauss, "Reducing the Effect of Spurious Phase Variations in Neural Oscillatory Signals," Frontiers in Computational Neuroscience, vol. 2018:12, iss. 82, pp. 1-16, 2018. doi:10.3389/fncom.2018.00082
    [BibTeX] [Abstract]
    The phase-reset model of oscillatory EEG activity has received a lot of attention in the last decades for decoding different cognitive processes. Based on this model, the ERPs are assumed to be generated as a result of phase reorganization in ongoing EEG. Alignment of the phase of neuronal activities can be observed within or between different assemblies of neurons across the brain. Phase synchronization has been used to explore and understand perception, attentional binding and considering it in the domain of neuronal correlates of consciousness. The importance of the topic and its vast exploration in different domains of the neuroscience presses the need for appropriate tools and methods for measuring the level of phase synchronization of neuronal activities. Measuring the level of instantaneous phase (IP) synchronization has been used extensively in numerous studies of ERPs as well as oscillatory activity for a better understanding of the underlying cognitive binding with regard to different set of stimulations such as auditory and visual. However, the reliability of results can be challenged as a result of noise artifact in IP. Phase distortion due to environmental noise artifacts as well as different pre-processing steps on signals can lead to generation of artificial phase jumps. One of such effects presented recently is the effect of low envelope on the IP of signal. It has been shown that as the instantaneous envelope of the analytic signal approaches zero, the variations in the phase increase, effectively leading to abrupt transitions in the phase. These abrupt transitions can distort the phase synchronization results as they are not related to any neurophysiological effect. These transitions are called spurious phase variation. In this study, we present a model to remove generated artificial phase variations due to the effect of low envelope. The proposed method is based on a simplified form of a Kalman smoother, that is able to model the IP behavior in narrow-bandpassed oscillatory signals. In this work we first explain the details of the proposed Kalman smoother for modeling the dynamics of the phase variations in narrow-bandpassed signals and then evaluate it on a set of synthetic signals. Finally, we apply the model on ongoing-EEG signals to assess the removal of spurious phase variations.
    @Article{mortezapouraghdamea2018,
      author    = {Mortezapouraghdam, Z. and Corona-Strauss, F. I. and Takahashi, T. and Strauss, D. J.},
      journal   = {Frontiers in Computational Neuroscience},
      title     = {Reducing the Effect of Spurious Phase Variations in Neural Oscillatory Signals},
      year      = {2018},
      month     = {oct},
      number    = {82},
      pages     = {1-16},
      volume    = {2018:12},
      abstract  = {The phase-reset model of oscillatory EEG activity has received a lot of attention in the last decades for decoding different cognitive processes. Based on this model, the ERPs are assumed to be generated as a result of phase reorganization in ongoing EEG. Alignment of the phase of neuronal activities can be observed within or between different assemblies of neurons across the brain. Phase synchronization has been used to explore and understand perception, attentional binding and considering it in the domain of neuronal correlates of consciousness. The importance of the topic and its vast exploration in different domains of the neuroscience presses the need for appropriate tools and methods for measuring the level of phase synchronization of neuronal activities. Measuring the level of instantaneous phase (IP) synchronization has been used extensively in numerous studies of ERPs as well as oscillatory activity for a better understanding of the underlying cognitive binding with regard to different set of stimulations such as auditory and visual. However, the reliability of results can be challenged as a result of noise artifact in IP. Phase distortion due to environmental noise artifacts as well as different pre-processing steps on signals can lead to generation of artificial phase jumps. One of such effects presented recently is the effect of low envelope on the IP of signal. It has been shown that as the instantaneous envelope of the analytic signal approaches zero, the variations in the phase increase, effectively leading to abrupt transitions in the phase. These abrupt transitions can distort the phase synchronization results as they are not related to any neurophysiological effect. These transitions are called spurious phase variation. In this study, we present a model to remove generated artificial phase variations due to the effect of low envelope. The proposed method is based on a simplified form of a Kalman smoother, that is able to model the IP behavior in narrow-bandpassed oscillatory signals. In this work we first explain the details of the proposed Kalman smoother for modeling the dynamics of the phase variations in narrow-bandpassed signals and then evaluate it on a set of synthetic signals. Finally, we apply the model on ongoing-EEG signals to assess the removal of spurious phase variations.},
      doi       = {10.3389/fncom.2018.00082},
      keywords  = {Instantaneous phase,Kalman smoother,Phase reset,Phase synchronization,Spurious phase},
      publisher = {Frontiers Media {SA}},
    }
  • C. Lehser, E. Wagner, and D. J. Strauss, "Somatosensory Evoked Responses Elicited by Haptic Sensations in Midair," IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 26, iss. 10, pp. 2070-2077, 2018. doi:10.1109/tnsre.2018.2869992
    [BibTeX] [Abstract]
    The design of human-machine interfaces (HMIs) by virtual haptics is an emerging field of research. So far, the perception of virtual haptic feedback, e.g., generated by focused ultrasound in midair has not been objectively evaluated. This paper demonstrates the feasibility of eliciting somatosensory evoked potentials (SEPs) with ultrasonic stimuli in midair for the first time. The palm was stimulated by short ultrasonic focal points generated by an ultrasound board. The results are compared with a no stimulation condition as well as with the results of a vibro tactile stimulation. The SEPs are analyzed with the wavelet phase synchronization stability (WPSS) and the M-consecutive averaged WPSS. The results indicate a clear SEP waveform elicited by ultrasound. It can be significantly differentiated from a no stimulation condition by the M-consecutive averaged WPSS. These results could enable the possibility of developing an objective evaluation method for virtual haptic feedback in HMIs.
    @Article{lehserea2018a,
      author    = {Lehser, C. and Wagner, E. and Strauss, D. J.},
      journal   = {{IEEE} Transactions on Neural Systems and Rehabilitation Engineering},
      title     = {Somatosensory Evoked Responses Elicited by Haptic Sensations in Midair},
      year      = {2018},
      month     = {oct},
      number    = {10},
      pages     = {2070-2077},
      volume    = {26},
      abstract  = {The design of human-machine interfaces (HMIs) by virtual haptics is an emerging field of research. So far, the perception of virtual haptic feedback, e.g., generated by focused ultrasound in midair has not been objectively evaluated. This paper demonstrates the feasibility of eliciting somatosensory evoked potentials (SEPs) with ultrasonic stimuli in midair for the first time. The palm was stimulated by short ultrasonic focal points generated by an ultrasound board. The results are compared with a no stimulation condition as well as with the results of a vibro tactile stimulation. The SEPs are analyzed with the wavelet phase synchronization stability (WPSS) and the M-consecutive averaged WPSS. The results indicate a clear SEP waveform elicited by ultrasound. It can be significantly differentiated from a no stimulation condition by the M-consecutive averaged WPSS. These results could enable the possibility of developing an objective evaluation method for virtual haptic feedback in HMIs.},
      doi       = {10.1109/tnsre.2018.2869992},
      keywords  = {Haptics,human-machine-interaction,somatosensory evoked potentials,ultrasound,wavelets},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • E. Schebsdat, M. C. Kohl, F. I. Corona-Strauss, H. Seidler, and D. J. Strauss, "Free-Field Evoked Auditory Brainstem Responses in Cochlear Implant Users," Audiology Research, vol. 8, iss. 2, pp. 44-53, 2018. doi:10.4081/audiores.2018.216
    [BibTeX] [Abstract]
    The importance of binaural cues in auditory stream formation and sound source segregation is widely accepted. When treating one ear with a cochlear implant (CI) the peripheral auditory system gets partially replaced and processing delays get added potentially, thus important interaural time differences get altered. However, these effects are not fully understood, leaving a lack of systematic binaural fitting strategies with respect to an optimal binaural fusion. To get new insights into such alterations, we suggest a novel method of free-field auditory brainstem evoked responses (ABRs) analysis in CI users. This method does not bypass the technically induced intrinsic delays of the sound processor while leaving the whole electrode array active, thus the most natural way of stimulation is provided. We compared the ABRs collected of 12 CI users and 12 normal hearing listeners using two different stimuli (chirp, click) at four different intensities each. We analyzed the ABRs using the average of 2000 trials as well as a single trial analysis and found consistent results in the ABRs' amplitudes and latencies, as well as in single trial relationships between both groups. This method provides a new perspective into the natural CI users' ABRs and can be useful in future research regarding binaural interaction and fusion.
    @Article{schebsdatea2018,
      author    = {Schebsdat, E. and Kohl, M. C. and Corona-Strauss, F. I. and Seidler, H. and Strauss, D. J.},
      journal   = {Audiology Research},
      title     = {Free-Field Evoked Auditory Brainstem Responses in Cochlear Implant Users},
      year      = {2018},
      month     = {dec},
      number    = {2},
      pages     = {44-53},
      volume    = {8},
      abstract  = {The importance of binaural cues in auditory stream formation and sound source segregation is widely accepted. When treating one ear with a cochlear implant (CI) the peripheral auditory system gets partially replaced and processing delays get added potentially, thus important interaural time differences get altered. However, these effects are not fully understood, leaving a lack of systematic binaural fitting strategies with respect to an optimal binaural fusion. To get new insights into such alterations, we suggest a novel method of free-field auditory brainstem evoked responses (ABRs) analysis in CI users. This method does not bypass the technically induced intrinsic delays of the sound processor while leaving the whole electrode array active, thus the most natural way of stimulation is provided. We compared the ABRs collected of 12 CI users and 12 normal hearing listeners using two different stimuli (chirp, click) at four different intensities each. We analyzed the ABRs using the average of 2000 trials as well as a single trial analysis and found consistent results in the ABRs' amplitudes and latencies, as well as in single trial relationships between both groups. This method provides a new perspective into the natural CI users' ABRs and can be useful in future research regarding binaural interaction and fusion.},
      doi       = {10.4081/audiores.2018.216},
      publisher = {{MDPI} {AG}},
    }
  • M. Busse, N. Salafzoon, A. Kraegeloh, D. R. Stevens, and D. J. Strauss, Estimating the Effects of Nanoparticles on Neuronal Field Potentials Based on Their Effects on Single Neurons In Vitro, F. Santamaria and X. G. Peralta, Eds., New York, NY: Springer New York, 2018. doi:10.1007/978-1-4939-7584-6_10
    [BibTeX] [Abstract]
    The application of nanoparticles in medicine requires a rigorous examination of their safety in order to determine and predict their benefits and potential side effects. The aim of this study was to examine in vitro effects of coated silver-nanoparticles (cAg-NPs) on the excitability of single neuronal cells and to integrate those findings into an in silico model to predict their effects on neuronal circuits and finally on field potentials generated by those circuits. As a first step, patch-clamp experiments were performed on single cells to investigate the effects of nano-sized silver particles surrounded by an organic coating. The parameters that were altered by exposure to those nanoparticles were then determined through using the Hodgkin & Huxley model of the sodium current. As a next step, to predict possible changes in network signaling due to the applied cAg-NPs, those findings were integrated into a well-defined neuronal circuit of thalamocortical interactions in silico. The model was then extended to observe neural fields originating from activity of neurons exhibiting Hodgkin & Huxley type action potentials. As a last step, the loop between field potentials and its generators was closed to investigate how the neural field potentials influence the spike generation in neurons that are physically located within these fields, if this feedback causes relevant changes in the underlying neuronal signaling within the circuit, and most importantly if the cAg-NPs effects on single neurons of the network are strong enough to cause observable changes in the generated field potentials themselves.
    @Book{busse2018,
      author    = {Busse, M. and Salafzoon, N. and Kraegeloh, A. and Stevens, D. R. and Strauss, D. J.},
      editor    = {Santamaria, F. and Peralta, X. G.},
      publisher = {Springer New York},
      title     = {Estimating the Effects of Nanoparticles on Neuronal Field Potentials Based on Their Effects on Single Neurons In Vitro},
      year      = {2018},
      address   = {New York, NY},
      abstract  = {The application of nanoparticles in medicine requires a rigorous examination of their safety in order to determine and predict their benefits and potential side effects. The aim of this study was to examine in vitro effects of coated silver-nanoparticles (cAg-NPs) on the excitability of single neuronal cells and to integrate those findings into an in silico model to predict their effects on neuronal circuits and finally on field potentials generated by those circuits. As a first step, patch-clamp experiments were performed on single cells to investigate the effects of nano-sized silver particles surrounded by an organic coating. The parameters that were altered by exposure to those nanoparticles were then determined through using the Hodgkin & Huxley model of the sodium current. As a next step, to predict possible changes in network signaling due to the applied cAg-NPs, those findings were integrated into a well-defined neuronal circuit of thalamocortical interactions in silico. The model was then extended to observe neural fields originating from activity of neurons exhibiting Hodgkin & Huxley type action potentials. As a last step, the loop between field potentials and its generators was closed to investigate how the neural field potentials influence the spike generation in neurons that are physically located within these fields, if this feedback causes relevant changes in the underlying neuronal signaling within the circuit, and most importantly if the cAg-NPs effects on single neurons of the network are strong enough to cause observable changes in the generated field potentials themselves.},
      booktitle = {Use of Nanoparticles in Neuroscience},
      doi       = {10.1007/978-1-4939-7584-6_10},
      keywords  = {Coated silver nanoparticles,Llin{\'{a}}s model,Modeling,Neuromodulatory effect,Neuronal circuit model,Nonviral vectors,Patch clamp recordings},
      pages     = {149-169},
    }
  • P. Flotho, M. J. Bhamborae, L. Haab, and D. J. Strauss, "Lagrangian Motion Magnification revisited: Continuous, Magnitude Driven Motion Scaling for Psychophysiological Experiments," in 2018 40th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2018. doi:10.1109/embc.2018.8512892
    [BibTeX] [Abstract]
    Video motion magnification forms a relatively novel family of visualization techniques, that aim to magnify imperceivably small motions in videos. The most prominent techniques are based on Eulerian video processing and local phase shifting, which modify pixel time courses, rather than relying on explicit motion estimation.In this work, we show that under ideal conditions in the context of psychophysiological experiments, a Lagrangian motion magnification approach based on dense optical flow estimation, can be superior to Eulerian motion magnification strategies. We present a novel, continuous and motion magnitude driven forward warping scheme of small motions, which implements motion compensation and magnification into a single motion estimation step. Our approach does not rely on temporal filtering and works in the presence of large motion. It does not require the explicit identification of fast moving objects and more generally no segmentation and or matting in the image domain is necessary. We apply our method to the visualization of blinking related modulations in micro-saccadic eye movements ((i.a.. iridodonesis), pupil dilation (hippus) and micro-expression analysis.
    @InProceedings{flothoea2018,
      author    = {Flotho, P. and Bhamborae, M. J. and Haab, L. and Strauss, D. J.},
      booktitle = {2018 40th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Lagrangian Motion Magnification revisited: Continuous, Magnitude Driven Motion Scaling for Psychophysiological Experiments},
      year      = {2018},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {Video motion magnification forms a relatively novel family of visualization techniques, that aim to magnify imperceivably small motions in videos. The most prominent techniques are based on Eulerian video processing and local phase shifting, which modify pixel time courses, rather than relying on explicit motion estimation.In this work, we show that under ideal conditions in the context of psychophysiological experiments, a Lagrangian motion magnification approach based on dense optical flow estimation, can be superior to Eulerian motion magnification strategies. We present a novel, continuous and motion magnitude driven forward warping scheme of small motions, which implements motion compensation and magnification into a single motion estimation step. Our approach does not rely on temporal filtering and works in the presence of large motion. It does not require the explicit identification of fast moving objects and more generally no segmentation and or matting in the image domain is necessary. We apply our method to the visualization of blinking related modulations in micro-saccadic eye movements ((i.a.. iridodonesis), pupil dilation (hippus) and micro-expression analysis.},
      doi       = {10.1109/embc.2018.8512892},
      keywords  = {motion magnification, motion analysis, optical flow, psychophysiology, micro-saccade, micro-expression},
    }
  • A. Schroeer, F. I. Corona-Strauss, S. A. Hackley, and D. J. Strauss, "Electromyographic Signs Of Pinna Orienting To Transient Sounds," in Conf Proc IEEE Eng Med Biol Soc. 2018, 2018.
    [BibTeX]
    @inproceedings{schroeerea2018,
      author = {Schroeer, A. and Corona-Strauss, F. I. and Hackley, S. A. and Strauss, D. J.},
      title = {Electromyographic Signs Of Pinna Orienting To Transient Sounds},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc. 2018},
      year = {2018}
    }
  • D. Thinnes, D. G. M. Laubner, F. Dauth, I. Bagci, D. J. Strauss, and F. I. Corona-Strauss, "Autonomic Nervous System Correlates of Motion Sickness during Highly Automated Driving," in Conf Proc IEEE Eng Med Biol Soc. 2018, 2018.
    [BibTeX]
    @InProceedings{thinnesea2018,
      author    = {Thinnes, D. and Laubner, D. G. M. and Dauth, F. and Bagci, I. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc. 2018},
      title     = {Autonomic Nervous System Correlates of Motion Sickness during Highly Automated Driving},
      year      = {2018},
    }
  • F. I. Corona-Strauss, S. A. Hackley, R. Hannemann, and D. J. Strauss, "Spatial Auditory Attention Decoded By Means Of Sustained Electromyographic Postauricular Muscles Activity," in Conf Proc IEEE Eng Med Biol Soc. 2018, 2018.
    [BibTeX]
    @InProceedings{coronastraussea2018,
      author    = {Corona-Strauss, F. I. and Hackley, S. A. and Hannemann, R. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc. 2018},
      title     = {Spatial Auditory Attention Decoded By Means Of Sustained Electromyographic Postauricular Muscles Activity},
      year      = {2018},
    }
  • D. G. M. Laubner, D. Thinnes, P. Delarber, F. Dauth, I. Bagci, D. J. Strauss, and F. I. Corona-Strauss, "Phasic Electrodermal Response Evoked by Instantaneous Longitudinal Accelerations for a Self-Driving Car Environment," in Conf Proc IEEE Eng Med Biol Soc. 2018, 2018.
    [BibTeX]
    @InProceedings{laubnerea2018,
      author    = {Laubner, D. G. M. and Thinnes, D. and Delarber, P. and Dauth, F. and Bagci, I. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc. 2018},
      title     = {Phasic Electrodermal Response Evoked by Instantaneous Longitudinal Accelerations for a Self-Driving Car Environment},
      year      = {2018},
    }
  • C. Lehser and D. J. Strauss, "Attentional Corrleates in Somatosensory Evoked Potentials elicited by ultrasound in mid-air," in Eurohaptics 2018, 2018.
    [BibTeX]
    @inproceedings{lehserea2018b,
      author = {Lehser, C. and Strauss, D. J.},
      title = {Attentional Corrleates in Somatosensory Evoked Potentials elicited by ultrasound in mid-air},
      booktitle = {Eurohaptics 2018},
      year = {2018}
    }
  • C. Lehser and D. J. Strauss, "Somatosensory Attentional Correlates Elicited by Ultrasound in Mid-Air," in Conf Proc IEEE Eng Med Biol Soc. 2018, 2018.
    [BibTeX]
    @inproceedings{lehserea2018c,
      author = {Lehser, C. and Strauss, D. J.},
      title = {Somatosensory Attentional Correlates Elicited by Ultrasound in Mid-Air},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc. 2018},
      year = {2018}
    }
  • P. Schaefer, P. Delarber, D. G. M. Laubner, D. Thinnes, P. Flotho, F. Dauth, I. Bagci, F. I. Corona-Strauss, and D. J. Strauss, "Correlation of Subjective Motion Sickness Level with EEG Power Bands and Phase Amplitude Coupling," in Conf Proc IEEE Eng Med Biol Soc. 2018, 2018.
    [BibTeX]
    @inproceedings{schaeferea2018,
      author = {Schaefer, P. and Delarber, P. and Laubner, D. G. M. and Thinnes, D. and Flotho, P. and Dauth, F. and Bagci, I. and Corona-Strauss, F. I. and Strauss, D. J.},
      title = {Correlation of Subjective Motion Sickness Level with EEG Power Bands and Phase Amplitude Coupling},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc. 2018},
      year = {2018}
    }

2017

  • C. Bernarding, D. J. Strauss, R. Hannemann, H. Seidler, and F. I. Corona-Strauss, "Neurodynamic evaluation of hearing aid features using EEG correlates of listening effort," Cognitive Neurodynamics, vol. 1:2017, iss. 3, pp. 1-30, 2017. doi:10.1007/s11571-017-9425-5
    [BibTeX] [Abstract]
    In this study, we propose a novel estimate of listening effort using electroencephalographic data. This method is a translation of our past findings, gained from the evoked electroencephalographic activity, to the oscillatory EEG activity. To test this technique, electroencephalographic data from experienced hearing aid users with moderate hearing loss were recorded, wearing hearing aids. The investigated hearing aid settings were: a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off, and a setting using omnidirectional microphones without any noise reduction. The results suggest that the electroencephalographic estimate of listening effort seems to be a useful tool to map the exerted effort of the participants. In addition, the results indicate that a directional processing mode can reduce the listening effort in multitalker listening situations.
    @Article{bernea2017,
      author    = {Bernarding, C. and Strauss, D. J. and Hannemann, R. and Seidler, H. and Corona-Strauss, F. I.},
      journal   = {Cognitive Neurodynamics},
      title     = {Neurodynamic evaluation of hearing aid features using {EEG} correlates of listening effort},
      year      = {2017},
      month     = {feb},
      note      = {Open access at http://link.springer.com/article/10.1007/s11571-017-9425-5},
      number    = {3},
      pages     = {1-30},
      volume    = {1:2017},
      abstract  = {In this study, we propose a novel estimate of listening effort using electroencephalographic data. This method is a translation of our past findings, gained from the evoked electroencephalographic activity, to the oscillatory EEG activity. To test this technique, electroencephalographic data from experienced hearing aid users with moderate hearing loss were recorded, wearing hearing aids. The investigated hearing aid settings were: a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off, and a setting using omnidirectional microphones without any noise reduction. The results suggest that the electroencephalographic estimate of listening effort seems to be a useful tool to map the exerted effort of the participants. In addition, the results indicate that a directional processing mode can reduce the listening effort in multitalker listening situations.},
      doi       = {10.1007/s11571-017-9425-5},
      keywords  = {EEG,Hearing aids,Hearing loss,Listening effort},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • D. J. Strauss and A. L. Francis, "Toward a taxonomic model of attention in effortful listening," Cognitive, Affective, & Behavioral Neuroscience, vol. 17, iss. 4, pp. 1-17, 2017. doi:10.3758/s13415-017-0513-0
    [BibTeX] [Abstract]
    In recent years, there has been increasing interest in studying listening effort. Research on listening effort intersects with the development of active theories of speech perception and contributes to the broader endeavor of understanding speech perception within the context of neuroscientific theories of perception, attention, and effort. Due to the multidisciplinary nature of the problem, researchers vary widely in their precise conceptualization of the catch-all term listening effort. Very recent consensus work stresses the relationship between listening effort and the allocation of cognitive resources, providing a conceptual link to current cognitive neuropsychological theories associating effort with the allocation of selective attention. By linking listening effort to attentional effort, we enable the application of a taxonomy of external and internal attention to the characterization of effortful listening. More specifically, we use a vectorial model to decompose the demand causing listening effort into its mutually orthogonal external and internal components and map the relationship between demanded and exerted effort by means of a resource-limiting term that can represent the influence of motivation as well as vigilance and arousal. Due to its quantitative nature and easy graphical interpretation, this model can be applied to a broad range of problems dealing with listening effort. As such, we conclude that the model provides a good starting point for further research on effortful listening within a more differentiated neuropsychological framework.
    @Article{straea2017,
      author    = {Strauss, D. J. and Francis, A. L.},
      journal   = {Cognitive, Affective, {\&} Behavioral Neuroscience},
      title     = {Toward a taxonomic model of attention in effortful listening},
      year      = {2017},
      month     = {may},
      number    = {4},
      pages     = {1-17},
      volume    = {17},
      abstract  = {In recent years, there has been increasing interest in studying listening effort. Research on listening effort intersects with the development of active theories of speech perception and contributes to the broader endeavor of understanding speech perception within the context of neuroscientific theories of perception, attention, and effort. Due to the multidisciplinary nature of the problem, researchers vary widely in their precise conceptualization of the catch-all term listening effort. Very recent consensus work stresses the relationship between listening effort and the allocation of cognitive resources, providing a conceptual link to current cognitive neuropsychological theories associating effort with the allocation of selective attention. By linking listening effort to attentional effort, we enable the application of a taxonomy of external and internal attention to the characterization of effortful listening. More specifically, we use a vectorial model to decompose the demand causing listening effort into its mutually orthogonal external and internal components and map the relationship between demanded and exerted effort by means of a resource-limiting term that can represent the influence of motivation as well as vigilance and arousal. Due to its quantitative nature and easy graphical interpretation, this model can be applied to a broad range of problems dealing with listening effort. As such, we conclude that the model provides a good starting point for further research on effortful listening within a more differentiated neuropsychological framework.},
      doi       = {10.3758/s13415-017-0513-0},
      keywords  = {Attention,Listening effort,Modeling,Speech perception},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • N. Özgün, D. J. Strauss, and R. Bennewitz, "Tribology of a Braille Display and EEG Correlates," Tribology Letters, vol. 66, iss. 1, p. 16, 2017. doi:10.1007/s11249-017-0969-7
    [BibTeX] [Abstract]
    Friction forces between human fingertip and a Braille display were recorded simultaneously with electroencephalographic (EEG) signals related to the somatosensory cortex. The correlation between frictional stimuli and event-related EEG signals was analyzed. Raising and lowering the dots of the Braille display caused significant N50 and P110 waves in the event-related EEG signal, but variations in the force stimulus by a factor of two between different Braille pattern did not cause significant differences in the EEG responses related to early tactile processing. Raising and lowering the dots of the Braille display triggers a characteristic temporal development of friction due to viscoelastic skin relaxation.
    @Article{ozgunea2017,
      author    = {{\"O}zg{\"u}n, N. and Strauss, D. J. and Bennewitz, R.},
      journal   = {Tribology Letters},
      title     = {Tribology of a Braille Display and {EEG} Correlates},
      year      = {2017},
      month     = {dec},
      number    = {1},
      pages     = {16},
      volume    = {66},
      abstract  = {Friction forces between human fingertip and a Braille display were recorded simultaneously with electroencephalographic (EEG) signals related to the somatosensory cortex. The correlation between frictional stimuli and event-related EEG signals was analyzed. Raising and lowering the dots of the Braille display caused significant N50 and P110 waves in the event-related EEG signal, but variations in the force stimulus by a factor of two between different Braille pattern did not cause significant differences in the EEG responses related to early tactile processing. Raising and lowering the dots of the Braille display triggers a characteristic temporal development of friction due to viscoelastic skin relaxation.},
      doi       = {10.1007/s11249-017-0969-7},
      keywords  = {Braille,Electroencephalography,Fingertip friction,Haptics,Perception,Touch},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • F. I. Corona-Strauss and D. J. Strauss, "Circular organization of the instantaneous phase in ERPs and the ongoing EEG due to selective attention," in 2017 8th International IEEE/EMBS Conference on Neural Engineering (NER), 2017. doi:10.1109/ner.2017.8008429
    [BibTeX] [Abstract]
    It is known that signs of early auditory selective attention are reflected in the N1-wave of auditory late potentials. In recent years, we used instantaneous phase synchronization measures related to this N1-effect to assess the attentional effort in listening. In particular, we showed that listening effort induced by task difficulty can be quantified by using this method. Subsequently, in order to not be restricted to short transient stimuli in event-related paradigms, we translated the idea of an objective listening effort estimation to the ongoing EEG activity CP in arbitrary, non-event-related listening tasks. Here we could again quantify effortful listening by analyzing the circular organization of the ongoing instantaneous phase. In this paper, we apply for the first time circular measures to segmented ERP and unsegmented EEG data from a repetition of the seminal dichotic tone detection experiment of Hillyard et al. who first described the N1-effect. In particular, we show that correlates of selective attention can be extracted from both data types by assessing the organization of the instantaneous phase. It is concluded that our study suggests a unified framework to analyze neural correlates of selective attention in ERPs and the ongoing EEG activity CP.
    @InProceedings{coroea2017,
      author    = {Corona-Strauss, F. I. and Strauss, D. J.},
      booktitle = {2017 8th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Circular organization of the instantaneous phase in {ERPs} and the ongoing {EEG} due to selective attention},
      year      = {2017},
      month     = {may},
      publisher = {{IEEE}},
      abstract  = {It is known that signs of early auditory selective attention are reflected in the N1-wave of auditory late potentials. In recent years, we used instantaneous phase synchronization measures related to this N1-effect to assess the attentional effort in listening. In particular, we showed that listening effort induced by task difficulty can be quantified by using this method. Subsequently, in order to not be restricted to short transient stimuli in event-related paradigms, we translated the idea of an objective listening effort estimation to the ongoing EEG activity CP in arbitrary, non-event-related listening tasks. Here we could again quantify effortful listening by analyzing the circular organization of the ongoing instantaneous phase. In this paper, we apply for the first time circular measures to segmented ERP and unsegmented EEG data from a repetition of the seminal dichotic tone detection experiment of Hillyard et al. who first described the N1-effect. In particular, we show that correlates of selective attention can be extracted from both data types by assessing the organization of the instantaneous phase. It is concluded that our study suggests a unified framework to analyze neural correlates of selective attention in ERPs and the ongoing EEG activity CP.},
      doi       = {10.1109/ner.2017.8008429},
    }
  • P. Flotho, A. E. Romero-Santiago, K. Schwerdtfeger, M. Hülser, and D. J. Strauss, "Energy based selective averaging approach for multi-trial optical imaging recordings," in 2017 IEEE 14th International Symposium on Biomedical Imaging (ISBI 2017), 2017. doi:10.1109/isbi.2017.7950511
    [BibTeX] [Abstract]
    Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of invasive neuroimaging techniques, that possess up to date the highest temporal and spatial resolution on a meso- to macroscopic scale.
    @InProceedings{flotea2017a,
      author    = {Flotho, P. and Romero-Santiago, A. E. and Schwerdtfeger, K. and H\"{u}lser, M. and Strauss, D. J.},
      booktitle = {2017 {IEEE} 14th International Symposium on Biomedical Imaging ({ISBI} 2017)},
      title     = {Energy based selective averaging approach for multi-trial optical imaging recordings},
      year      = {2017},
      month     = {apr},
      publisher = {{IEEE}},
      abstract  = {Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of invasive neuroimaging techniques, that possess up to date the highest temporal and spatial resolution on a meso- to macroscopic scale.},
      doi       = {10.1109/isbi.2017.7950511},
      keywords  = {Denoising,Image Registration,Intrinsic Signals,Optical Imaging,VSD Imaging},
    }
  • P. Flotho and D. J. Strauss, "Quantitative motion analysis for non-contact affective and neurocognitive assessment," in 2017 8th International IEEE/EMBS Conference on Neural Engineering (NER), 2017. doi:10.1109/ner.2017.8008303
    [BibTeX] [Abstract]
    Qualitative motion analysis with motion magnification techniques opened a new dimension to videos by revealing imperceptible information hidden in small movements. Those movements can contain information on neurocognitive and affective states and thus could be a novel source of information during driving or neurocognitive experiments, complementing secondary sensors in the respective setup.
    @InProceedings{flotea2017b,
      author    = {Flotho, P. and Strauss, D. J.},
      booktitle = {2017 8th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Quantitative motion analysis for non-contact affective and neurocognitive assessment},
      year      = {2017},
      month     = {may},
      publisher = {{IEEE}},
      abstract  = {Qualitative motion analysis with motion magnification techniques opened a new dimension to videos by revealing imperceptible information hidden in small movements. Those movements can contain information on neurocognitive and affective states and thus could be a novel source of information during driving or neurocognitive experiments, complementing secondary sensors in the respective setup.},
      doi       = {10.1109/ner.2017.8008303},
      keywords  = {Dense Optical Flow,Non-contact neurocognitive assessment,Scene Flow},
    }
  • E. Schebsdat, D. J. Strauss, and J. Wolfe, "Objective Evaluation of the Subjectively Perceived Loudness of Cochlear-Implant Users," in Neural Engineering (NER), 8th International IEEE/EMBS Conference on, 2017.
    [BibTeX]
    @inproceedings{scheea2017,
      author = {Schebsdat, E. and Strauss, D. J. and Wolfe, J.},
      title = {Objective Evaluation of the Subjectively Perceived Loudness of Cochlear-Implant Users},
      booktitle = {Neural Engineering (NER), 8th International IEEE/EMBS Conference on},
      year = {2017}
    }
  • Z. Mortezapouraghdam and D. J. Strauss, "Removal of spurious phase variations in oscillatory signals," in 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2017. doi:10.1109/embc.2017.8037293
    [BibTeX] [Abstract]
    The study of oscillatory electroencephalogram (EEG) data has been one of the main sources for the analysis of different brain functions and decoding a variety of cognitive processes. One of the interesting features that has been the focus of study in the last decades is the study of instantaneous phase information in EEG. Phase synchronization techniques are among the main analysis tools that measure the degree of phase re-organization in signals. In phase re-organization approach, the phase alignment in stimulus induced potentials has been shown to be informative for decoding cognitive processes. Despite the developments in this area, the precision of measures may vary based on the level of noise. Phase distortion due to artefacts and a variety of pre-processing steps that are applied on data, can introduce artificial phase alignment. These artificial phase variations (that is referred to spurious phase variations) are not correlated to any stimulus or event. In a new study, it has been showed that a low instantaneous envelope lead to abrupt changes in IP, which could distort the results of phase synchronization. In this work, we propose a method that is able to estimate the true phase based on the measurements and estimate a standard deviation for the computed phase. The method enables to remove the effect of artificial phase changes due to low envelope. In this approach the analytic signal is modeled by a Kalman smoother, and estimates a more reliable version of the IP from the measurements. At last, we evaluate the model on different synthetic data sets.
    @InProceedings{mortea2017a,
      author    = {Mortezapouraghdam, Z. and Strauss, D. J.},
      booktitle = {2017 39th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Removal of spurious phase variations in oscillatory signals},
      year      = {2017},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {The study of oscillatory electroencephalogram (EEG) data has been one of the main sources for the analysis of different brain functions and decoding a variety of cognitive processes. One of the interesting features that has been the focus of study in the last decades is the study of instantaneous phase information in EEG. Phase synchronization techniques are among the main analysis tools that measure the degree of phase re-organization in signals. In phase re-organization approach, the phase alignment in stimulus induced potentials has been shown to be informative for decoding cognitive processes. Despite the developments in this area, the precision of measures may vary based on the level of noise. Phase distortion due to artefacts and a variety of pre-processing steps that are applied on data, can introduce artificial phase alignment. These artificial phase variations (that is referred to spurious phase variations) are not correlated to any stimulus or event. In a new study, it has been showed that a low instantaneous envelope lead to abrupt changes in IP, which could distort the results of phase synchronization. In this work, we propose a method that is able to estimate the true phase based on the measurements and estimate a standard deviation for the computed phase. The method enables to remove the effect of artificial phase changes due to low envelope. In this approach the analytic signal is modeled by a Kalman smoother, and estimates a more reliable version of the IP from the measurements. At last, we evaluate the model on different synthetic data sets.},
      doi       = {10.1109/embc.2017.8037293},
    }
  • P. Flotho, A. E. Romero-Santiago, K. Schwerdtfeger, M. Hülser, L. Haab, and D. J. Strauss, "Pyramid approach for the reduction of parallax-related artefacts in optical recordings of moving translucent volumes," in 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2017. doi:10.1109/embc.2017.8037834
    [BibTeX] [Abstract]
    Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of invasive neuroimaging techniques, that possess up to date the highest temporal and spatial resolution on a meso- to macroscopic scale. There are different sources that contribute to the OI signal of which many are noise. In our previous works, we have used dense optical flow for the reduction of movement artefacts. The translucent surface of the cortex allows contributions from multiple depths. Due to the depth of field (DOF) effect, we get an implicit relation of depth and 2D frequency components. In this work, we introduce registration on the levels of a Laplacian pyramid to remove movement artefacts which have different motion components in different spatial frequency bands. This aims to resolve artefacts that remain after normal registration and are caused e.g. by parallax motion, dead pixels or dust on the sensor and other high frequent, moving particles on the cortex surface without the compromise of using high smoothness weights.
    @InProceedings{flotea2017c,
      author    = {Flotho, P. and Romero-Santiago, A. E. and Schwerdtfeger, K. and H\"{u}lser, M. and Haab, L. and Strauss, D. J.},
      booktitle = {2017 39th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Pyramid approach for the reduction of parallax-related artefacts in optical recordings of moving translucent volumes},
      year      = {2017},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of invasive neuroimaging techniques, that possess up to date the highest temporal and spatial resolution on a meso- to macroscopic scale. There are different sources that contribute to the OI signal of which many are noise. In our previous works, we have used dense optical flow for the reduction of movement artefacts. The translucent surface of the cortex allows contributions from multiple depths. Due to the depth of field (DOF) effect, we get an implicit relation of depth and 2D frequency components. In this work, we introduce registration on the levels of a Laplacian pyramid to remove movement artefacts which have different motion components in different spatial frequency bands. This aims to resolve artefacts that remain after normal registration and are caused e.g. by parallax motion, dead pixels or dust on the sensor and other high frequent, moving particles on the cortex surface without the compromise of using high smoothness weights.},
      doi       = {10.1109/embc.2017.8037834},
      keywords  = {Denoising,Depth from Defocus,Image Registration,Laplacian Pyramid,Optical Imaging},
    }
  • Z. Mortezapouraghdam, D. J. Strauss, and C. Bernarding, "Objective assessment of perceived effort in listening by employing EEG feature," in 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2017. doi:10.1109/embc.2017.8037465
    [BibTeX] [Abstract]
    The adjustment of hearing aid devices can heavily depend on the subjective feedback of the patients. Our aim is to investigate measures that can be used objectively to state a subject's listening effort. To obtain a comprehensive and reliable measure as an indicator for a person's listening effort, we need to have a better understanding of electroencephalograpic (EEG) activities. Decoding EEG signals specifically by the analysis of the instantaneous phase information has been a new trend in the last decades. Throughout many studies conducted in the past, it has been shown that the instantaneous phase of oscillatory signals reset in relation to various cognitive processes. This is based on a hypothesis presented for the generation of event related potentials. In this study, we measure the degree of phase re-organization through fitting a von Mises distribution to EEG recordings. The concentration parameter of a von Mises distribution has been shown as an informative feature for reflecting the level of attention. This feature has been used for predicting the listening effort and the results are compared among three different hearing aid settings.
    @InProceedings{mortea2017b,
      author    = {Mortezapouraghdam, Z. and Strauss, D. J. and Bernarding, C.},
      booktitle = {2017 39th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Objective assessment of perceived effort in listening by employing {EEG} feature},
      year      = {2017},
      month     = {jul},
      publisher = {{IEEE}},
      abstract  = {The adjustment of hearing aid devices can heavily depend on the subjective feedback of the patients. Our aim is to investigate measures that can be used objectively to state a subject's listening effort. To obtain a comprehensive and reliable measure as an indicator for a person's listening effort, we need to have a better understanding of electroencephalograpic (EEG) activities. Decoding EEG signals specifically by the analysis of the instantaneous phase information has been a new trend in the last decades. Throughout many studies conducted in the past, it has been shown that the instantaneous phase of oscillatory signals reset in relation to various cognitive processes. This is based on a hypothesis presented for the generation of event related potentials. In this study, we measure the degree of phase re-organization through fitting a von Mises distribution to EEG recordings. The concentration parameter of a von Mises distribution has been shown as an informative feature for reflecting the level of attention. This feature has been used for predicting the listening effort and the results are compared among three different hearing aid settings.},
      doi       = {10.1109/embc.2017.8037465},
    }

2016

  • Z. Mortezapouraghdam, R. C. Wilson, L. Schwabe, and D. J. Strauss, "Bayesian Modeling of the Dynamics of Phase Modulations and their Application to Auditory Event Related Potentials at Different Loudness Scales," Frontiers in Computational Neuroscience, vol. 10, iss. 2, pp. 1-10, 2016. doi:10.3389/fncom.2016.00002
    [BibTeX] [Abstract]
    We study the effect of long-term habituation signatures of auditory selective attention reflected in the instantaneous phase information of the auditory event-related potentials (ERPs) at four distinct stimuli levels of 60, 70, 80, and 90 dB SPL. The analysis is based on the single-trial level. The effect of habituation can be observed in terms of the changes (jitter) in the instantaneous phase information of ERPs. In particular, the absence of habituation is correlated with a consistently high phase synchronization over ERP trials. We estimate the changes in phase concentration over trials using a Bayesian approach, in which the phase is modeled as being drawn from a von Mises distribution with a concentration parameter which varies smoothly over trials. The smoothness assumption reflects the fact that habituation is a gradual process. We differentiate between different stimuli based on the relative changes and absolute values of the estimated concentration parameter using the proposed Bayesian model.
    @Article{mortea2016,
      author    = {Mortezapouraghdam, Z. and Wilson, R. C. and Schwabe, L. and Strauss, D. J.},
      journal   = {Frontiers in Computational Neuroscience},
      title     = {Bayesian Modeling of the Dynamics of Phase Modulations and their Application to Auditory Event Related Potentials at Different Loudness Scales},
      year      = {2016},
      month     = {jan},
      number    = {2},
      pages     = {1-10},
      volume    = {10},
      abstract  = {We study the effect of long-term habituation signatures of auditory selective attention reflected in the instantaneous phase information of the auditory event-related potentials (ERPs) at four distinct stimuli levels of 60, 70, 80, and 90 dB SPL. The analysis is based on the single-trial level. The effect of habituation can be observed in terms of the changes (jitter) in the instantaneous phase information of ERPs. In particular, the absence of habituation is correlated with a consistently high phase synchronization over ERP trials. We estimate the changes in phase concentration over trials using a Bayesian approach, in which the phase is modeled as being drawn from a von Mises distribution with a concentration parameter which varies smoothly over trials. The smoothness assumption reflects the fact that habituation is a gradual process. We differentiate between different stimuli based on the relative changes and absolute values of the estimated concentration parameter using the proposed Bayesian model.},
      doi       = {10.3389/fncom.2016.00002},
      keywords  = {Bayesian models,Circular,Event-related potentials,Instantaneous phase,Long-term habituation},
      publisher = {Frontiers Media {SA}},
    }
  • D. J. Strauss, H. Seidler, F. I. Corona-Strauss, L. Haab, and R. Hannemann, "Notched environmental sounds: a new hearing aid-supported tinnitus treatment evaluated in 20 patients," Clinical Otolaryngology, vol. 42, iss. 1, pp. 1172-175, 2016. doi:10.1111/coa.12575
    [BibTeX]
    @Article{straea2016,
      author    = {Strauss, D. J. and Seidler, H. and Corona-Strauss, F. I. and Haab, L. and Hannemann, R.},
      journal   = {Clinical Otolaryngology},
      title     = {Notched environmental sounds: a new hearing aid-supported tinnitus treatment evaluated in 20 patients},
      year      = {2016},
      month     = {feb},
      number    = {1},
      pages     = {1172-175},
      volume    = {42},
      doi       = {10.1111/coa.12575},
      publisher = {Wiley},
    }
  • M. C. Kohl and D. J. Strauss, "A compact representation for the auditory full-range response and its fast denoising using an image filter based on the Radon Transform," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 5877-5880. doi:10.1109/embc.2016.7592065
    [BibTeX] [Abstract]
    The Auditory Brainstem, Middle-Latency and Late Responses, a class of event-related potentials (ERPs), are of considerable interest in neuroscience research as robust neural correlates of different processing stages along the auditory pathway. While most research to date centers around one of the responses at a time for practical reasons, recent efforts indicate a paradigm shift towards acquiring them together, enabling the simultaneous monitoring of all auditory processing stages from the brainstem to the cortex. In this paper, we introduce a compact representation for this Auditory Full-Range Response (AFRR) as an ERP map with adaptive sampling rate, making it suitable for computationally inexpencive image filtering. Furthermore, we propose a novel algorithm for the fast denoising of such ERP maps based on the Radon Transform and its inversion by filtered backprojection. Its performance is compared qualitatively to a Gaussian means filter using a real-world chirp-evoked AFRR recording. The algorithm exhibits good noise suppression as well as high preservance of the single-response structure, making it a promising denoising tool for future ERP studies.
    @InProceedings{kohlea2016,
      author    = {Kohl, M. C. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {A compact representation for the auditory full-range response and its fast denoising using an image filter based on the Radon Transform},
      year      = {2016},
      month     = {aug},
      pages     = {5877-5880},
      publisher = {{IEEE}},
      abstract  = {The Auditory Brainstem, Middle-Latency and Late Responses, a class of event-related potentials (ERPs), are of considerable interest in neuroscience research as robust neural correlates of different processing stages along the auditory pathway. While most research to date centers around one of the responses at a time for practical reasons, recent efforts indicate a paradigm shift towards acquiring them together, enabling the simultaneous monitoring of all auditory processing stages from the brainstem to the cortex. In this paper, we introduce a compact representation for this Auditory Full-Range Response (AFRR) as an ERP map with adaptive sampling rate, making it suitable for computationally inexpencive image filtering. Furthermore, we propose a novel algorithm for the fast denoising of such ERP maps based on the Radon Transform and its inversion by filtered backprojection. Its performance is compared qualitatively to a Gaussian means filter using a real-world chirp-evoked AFRR recording. The algorithm exhibits good noise suppression as well as high preservance of the single-response structure, making it a promising denoising tool for future ERP studies.},
      doi       = {10.1109/embc.2016.7592065},
    }
  • F. I. Corona-Strauss and D. J. Strauss, "Robust extraction of the N1-effect in dichotic listening using hardy space mappings of auditory late single trials," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 3418-3421. doi:10.1109/embc.2016.7591462
    [BibTeX] [Abstract]
    It is known that signs of (early) auditory selective attention are reflected in the N1-wave of auditory late potentials. In recent years, we have analyzed this N1-effect using multiscale neurofunctional modeling and (instantaneous) phase synchronization measures of Hardy space mapped data. To acquire the electroencephalographic data in dichotic listening, we repeated the seminal experiment of Hillyard et al. which first described the N1-effect. Here we apply for the first time phase synchronization measures to these dichotic data and compare the results to the conventional time-domain analysis. Our results suggest that a single trial synchronization analysis of the instantaneous phase at the $\alpha$/$\theta$-border shows the N1-attention effect even more clear than the original averaged time-domain representation. It is concluded that the presented method is a robust tool to analyse (early) signs of selective attention in dichotic listening tasks.
    @InProceedings{coroea2016,
      author    = {Corona-Strauss, F. I. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Robust extraction of the N1-effect in dichotic listening using hardy space mappings of auditory late single trials},
      year      = {2016},
      month     = {aug},
      pages     = {3418-3421},
      publisher = {{IEEE}},
      abstract  = {It is known that signs of (early) auditory selective attention are reflected in the N1-wave of auditory late potentials. In recent years, we have analyzed this N1-effect using multiscale neurofunctional modeling and (instantaneous) phase synchronization measures of Hardy space mapped data. To acquire the electroencephalographic data in dichotic listening, we repeated the seminal experiment of Hillyard et al. which first described the N1-effect. Here we apply for the first time phase synchronization measures to these dichotic data and compare the results to the conventional time-domain analysis. Our results suggest that a single trial synchronization analysis of the instantaneous phase at the $\alpha$/$\theta$-border shows the N1-attention effect even more clear than the original averaged time-domain representation. It is concluded that the presented method is a robust tool to analyse (early) signs of selective attention in dichotic listening tasks.},
      doi       = {10.1109/embc.2016.7591462},
    }
  • E. Schebsdat, H. Hessel, H. Seidler, and D. J. Strauss, "Detection of binaural interaction in free-field evoked auditory brainstem responses by time-scale representations," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 3732-3735. doi:10.1109/embc.2016.7591539
    [BibTeX] [Abstract]
    The so called $\beta$-wave of the binaural interaction component (BIC) in auditory brainstem responses (ABR) has been shown to be an objective measure for binaural interaction (BI). This component is the arithmetical difference between the sum of the monaurally evoked ABRs and the binaurally evoked ABR. Unfortunately, these neural responses are known to be very fragile and as a result the calculated BIC. An additional issue is, that the findings of this measurement are predominantly needed in people with hearing loss who may use hearing devices like hearing aids (HA) or cochlear implants (CI), thus they are not able to use headphones (like in conventional ABR measurements) during the detection of possible BI. This is a crucial problem, because it is known that factors like the interaural time delay (ITD) between the receiving ears are responsible for solving tasks like sound source localization or sound source separation, but specially designed measurements to coordinate the fitting of HAs or CIs with respect to BI are still missing. In this paper, we introduce a new measurement setup that is able to detect BI depending on different ITDs in free-field evoked responses by using the more reliable instantaneous phase in the time-scale representation. With this pilot study we are able to demonstrate a decreasing BI with an increasing ITD using the wavelet phase synchronization stability analysis in ten normal hearing subjects.
    @InProceedings{scheea2016,
      author    = {Schebsdat, E. and Hessel, H. and Seidler, H. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Detection of binaural interaction in free-field evoked auditory brainstem responses by time-scale representations},
      year      = {2016},
      month     = {aug},
      pages     = {3732-3735},
      publisher = {{IEEE}},
      abstract  = {The so called $\beta$-wave of the binaural interaction component (BIC) in auditory brainstem responses (ABR) has been shown to be an objective measure for binaural interaction (BI). This component is the arithmetical difference between the sum of the monaurally evoked ABRs and the binaurally evoked ABR. Unfortunately, these neural responses are known to be very fragile and as a result the calculated BIC. An additional issue is, that the findings of this measurement are predominantly needed in people with hearing loss who may use hearing devices like hearing aids (HA) or cochlear implants (CI), thus they are not able to use headphones (like in conventional ABR measurements) during the detection of possible BI. This is a crucial problem, because it is known that factors like the interaural time delay (ITD) between the receiving ears are responsible for solving tasks like sound source localization or sound source separation, but specially designed measurements to coordinate the fitting of HAs or CIs with respect to BI are still missing. In this paper, we introduce a new measurement setup that is able to detect BI depending on different ITDs in free-field evoked responses by using the more reliable instantaneous phase in the time-scale representation. With this pilot study we are able to demonstrate a decreasing BI with an increasing ITD using the wavelet phase synchronization stability analysis in ten normal hearing subjects.},
      doi       = {10.1109/embc.2016.7591539},
    }
  • A. E. Uriarte, L. Haab, N. Salafzoon, and D. J. Strauss, "Thalamic gamma band desynchronization in a computational model of the auditory pathway," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 1409-1412. doi:10.1109/embc.2016.7590972
    [BibTeX] [Abstract]
    Recent studies have focused on modeling the response of the early auditory processing stages to sound stimuli. However, the influence of sound on the higher stages like the auditory thalamus are not well identified. To understand how different sound stimuli affect the response of neurons in these higher stages, it is necessary to model the auditory pathway from the auditory nerve (AN) through the different stages up to the cortex. In this article we present a model of one of the paths through which sound travels from the AN to the cortex. The model presented is a compound of several sub models of different stages of the auditory pathway which offers a detailed resolution due to the subsequent simulation of processing stages. We consider neurons from the AN, the dorsal cochlear nucleus (DCN), the thalamus (specific and non-specific thalamic cells and reticular nucleus) and cortical columns simulating attended and unattended conditions. We use pure tone stimuli with different frequencies as an input and analyze the power spectra of the thalamic and cortical neurons. The main difference in the power spectra can be seen in the specific thalamic cells (STC), where a clear loss of power in the gamma band of the neurons responsible for processing the sound input occurred.
    @InProceedings{uriaea2016,
      author    = {Uriarte, A. E. and Haab, L. and Salafzoon, N. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Thalamic gamma band desynchronization in a computational model of the auditory pathway},
      year      = {2016},
      month     = {aug},
      pages     = {1409-1412},
      publisher = {{IEEE}},
      abstract  = {Recent studies have focused on modeling the response of the early auditory processing stages to sound stimuli. However, the influence of sound on the higher stages like the auditory thalamus are not well identified. To understand how different sound stimuli affect the response of neurons in these higher stages, it is necessary to model the auditory pathway from the auditory nerve (AN) through the different stages up to the cortex. In this article we present a model of one of the paths through which sound travels from the AN to the cortex. The model presented is a compound of several sub models of different stages of the auditory pathway which offers a detailed resolution due to the subsequent simulation of processing stages. We consider neurons from the AN, the dorsal cochlear nucleus (DCN), the thalamus (specific and non-specific thalamic cells and reticular nucleus) and cortical columns simulating attended and unattended conditions. We use pure tone stimuli with different frequencies as an input and analyze the power spectra of the thalamic and cortical neurons. The main difference in the power spectra can be seen in the specific thalamic cells (STC), where a clear loss of power in the gamma band of the neurons responsible for processing the sound input occurred.},
      doi       = {10.1109/embc.2016.7590972},
    }
  • P. Flotho, A. E. Romero-Santiago, K. Schwerdtfeger, J. Szczygielski, M. Hülser, L. Haab, and D. J. Strauss, "Motion invariant contrast enhancement of optical imaging data in the gradient domain," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 3937-3940. doi:10.1109/embc.2016.7591588
    [BibTeX] [Abstract]
    Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of neuroimaging techniques that possess up to date highest temporal and spatial resolution on a meso-to macroscopic scale. An inherent problem of OI is a very low signal to noise ratio (SNR), which restricts the recordings to be completely motionless and requires detailed knowledge of the properties of the different noise sources. In our experiments we performed a durectomy and did not use an imaging chamber to allow us future joint electroencephalography-optical imaging (EEG-OI) measures, which resulted in movement artifacts. With the goal of motion compensation in OI recordings and magnification of signal changes, we present a novel processing pipeline, which is based on optic flow guided denoising and gradient domain tone mapping for spatiotemporal contrast enhancement.
    @InProceedings{flotea2016,
      author    = {Flotho, P. and Romero-Santiago, A. E. and Schwerdtfeger, K. and Szczygielski, J. and H\"{u}lser, M. and Haab, L. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Motion invariant contrast enhancement of optical imaging data in the gradient domain},
      year      = {2016},
      month     = {aug},
      pages     = {3937-3940},
      publisher = {{IEEE}},
      abstract  = {Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of neuroimaging techniques that possess up to date highest temporal and spatial resolution on a meso-to macroscopic scale. An inherent problem of OI is a very low signal to noise ratio (SNR), which restricts the recordings to be completely motionless and requires detailed knowledge of the properties of the different noise sources. In our experiments we performed a durectomy and did not use an imaging chamber to allow us future joint electroencephalography-optical imaging (EEG-OI) measures, which resulted in movement artifacts. With the goal of motion compensation in OI recordings and magnification of signal changes, we present a novel processing pipeline, which is based on optic flow guided denoising and gradient domain tone mapping for spatiotemporal contrast enhancement.},
      doi       = {10.1109/embc.2016.7591588},
      keywords  = {Denoising,Image Registration,Intrinsic Signals,Optical Imaging,VSDI},
    }
  • A. E. Romero-Santiago, P. Flotho, K. Schwerdtfeger, J. Szczygielski, M. Hülser, L. Haab, and D. J. Strauss, "Compensation of pulsation artifacts during optical imaging with and without cranial chamber," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 5921-5924. doi:10.1109/embc.2016.7592076
    [BibTeX] [Abstract]
    Functional Optical Imaging (OI) through the opened skull forms a group of Neuroimaging techniques characterized by a high temporal and spatial resolution on a meso-to macroscopic scale. State of the art OI experiments are generally difficult to execute, with a very timely surgical preparation preceding the experiment, that requires a skilled surgeon to mount a sealed imaging chamber onto the skull. The chamber reduces brain pulsation artifacts and swelling of the brain through movement restriction. In this work, we present preliminary results of a novel approach that does not rely on the usage of an imaging chamber with the goal to facilitate heavily the surgical animal preparation and to allow straightforward joint Electroencephalography - Optical Imaging recordings in the future. We carried out experiments to compare the movement restricting properties of the imaging chamber with the movement in a recording of an unconstrained and periodically irrigated brain. We used high-level image processing techniques to reduce brain pulsation artifacts and did a quantitative movement analysis of the recordings. Our results suggest that while recordings with imaging chamber show less sagittal movement, both with and without imaging chamber comprise the same lateral movements.
    @InProceedings{romeea2016,
      author    = {Romero-Santiago, A. E. and Flotho, P. and Schwerdtfeger, K. and Szczygielski, J. and H\"{u}lser, M. and Haab, L. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Compensation of pulsation artifacts during optical imaging with and without cranial chamber},
      year      = {2016},
      month     = {aug},
      pages     = {5921-5924},
      publisher = {{IEEE}},
      abstract  = {Functional Optical Imaging (OI) through the opened skull forms a group of Neuroimaging techniques characterized by a high temporal and spatial resolution on a meso-to macroscopic scale. State of the art OI experiments are generally difficult to execute, with a very timely surgical preparation preceding the experiment, that requires a skilled surgeon to mount a sealed imaging chamber onto the skull. The chamber reduces brain pulsation artifacts and swelling of the brain through movement restriction. In this work, we present preliminary results of a novel approach that does not rely on the usage of an imaging chamber with the goal to facilitate heavily the surgical animal preparation and to allow straightforward joint Electroencephalography - Optical Imaging recordings in the future. We carried out experiments to compare the movement restricting properties of the imaging chamber with the movement in a recording of an unconstrained and periodically irrigated brain. We used high-level image processing techniques to reduce brain pulsation artifacts and did a quantitative movement analysis of the recordings. Our results suggest that while recordings with imaging chamber show less sagittal movement, both with and without imaging chamber comprise the same lateral movements.},
      doi       = {10.1109/embc.2016.7592076},
    }
  • C. Bernarding, F. I. Corona-Strauss, R. Hannemann, and D. J. Strauss, "Objective assessment of listening effort: Effects of an increased task demand," in 2016 38th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2016, pp. 3684-3687. doi:10.1109/embc.2016.7591527
    [BibTeX] [Abstract]
    In demanding listening situations the individual has to exert an increased listening effort to process interesting auditory signals correctly. Especially people with hearing loss are particularly affected and require more effort to identify sounds compared to those with normal hearing. So far, a suitable objective estimate of listening effort is still not available. In previous studies, we presented an objective estimate of listening effort (OLEosc), which is based on the instantaneous phase distribution of the ongoing EEG activity. In the current study, the proposed measure was analyzed in detail. The task performance was taken into account, which indicates if the participants can solve the auditory task and exert effort or if they ceased solving the task. The EEG data was acquired from people with moderate hearing loss solving a listening task. During the experiment, hearing aid settings with different microphone configurations were tested. The results indicate that the OLEosc reflects the real exerted effort of the participants. Besides the reflection of different task demands related to the hearing aid settings, it was possible to show a decline of focused attention to the auditory stimuli related to an excessive task demand. Furthermore, the data indicate that the OLEosc is not directly correlated to the speech intelligibility presented in the word score data and is not subjectively biased like the results of the presented rating scale.
    @InProceedings{bernea2016,
      author    = {Bernarding, C. and Corona-Strauss, F. I. and Hannemann, R. and Strauss, D. J.},
      booktitle = {2016 38th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Objective assessment of listening effort: Effects of an increased task demand},
      year      = {2016},
      month     = {aug},
      pages     = {3684-3687},
      publisher = {{IEEE}},
      abstract  = {In demanding listening situations the individual has to exert an increased listening effort to process interesting auditory signals correctly. Especially people with hearing loss are particularly affected and require more effort to identify sounds compared to those with normal hearing. So far, a suitable objective estimate of listening effort is still not available. In previous studies, we presented an objective estimate of listening effort (OLEosc), which is based on the instantaneous phase distribution of the ongoing EEG activity. In the current study, the proposed measure was analyzed in detail. The task performance was taken into account, which indicates if the participants can solve the auditory task and exert effort or if they ceased solving the task. The EEG data was acquired from people with moderate hearing loss solving a listening task. During the experiment, hearing aid settings with different microphone configurations were tested. The results indicate that the OLEosc reflects the real exerted effort of the participants. Besides the reflection of different task demands related to the hearing aid settings, it was possible to show a decline of focused attention to the auditory stimuli related to an excessive task demand. Furthermore, the data indicate that the OLEosc is not directly correlated to the speech intelligibility presented in the word score data and is not subjectively biased like the results of the presented rating scale.},
      doi       = {10.1109/embc.2016.7591527},
    }
  • F. I. Corona-Strauss and D. J. Strauss, "Correlates of Selective Auditory Attention in Hardy-Space Projected Single-Trials," in HEAL - Hearing Across the Lifespan, 2016.
    [BibTeX]
    @inproceedings{coroea2016,
      author = {Corona-Strauss, F. I. and Strauss, D. J.},
      title = {Correlates of Selective Auditory Attention in Hardy-Space Projected Single-Trials},
      booktitle = {HEAL - Hearing Across the Lifespan},
      year = {2016}
    }
  • D. J. Strauss, C. Bernarding, R. Hannemann, R. L. Fischer, M. Serman, P. Schäfer, and F. I. Corona-Strauss, "EEG-aided Evaluation of Hearing Instrument Features Using Listening Effort Correlates," in HEAL - Hearing Across the Lifespan, 2016.
    [BibTeX]
    @inproceedings{straea2016,
      author = {Strauss, D. J. and Bernarding, C. and Hannemann, R. and Fischer, R. L. and Serman, M. and Sch\"{a}fer, P. and Corona-Strauss, F. I.},
      title = {EEG-aided Evaluation of Hearing Instrument Features Using Listening Effort Correlates},
      booktitle = {HEAL - Hearing Across the Lifespan},
      year = {2016}
    }
  • D. J. Strauss, J. K. Schubert, G. Steidl, and F. I. Corona-Strauss, "2D Phase-Denoising of Auditory Evoked and Event-Related Potential Single-Trials," in HEAL - Hearing Across the Lifespan, 2016.
    [BibTeX]
    @inproceedings{straea2016,
      author = {Strauss, D. J. and Schubert, J. K. and Steidl, G. and Corona-Strauss, F. I.},
      title = {2D Phase-Denoising of Auditory Evoked and Event-Related Potential Single-Trials},
      booktitle = {HEAL - Hearing Across the Lifespan},
      year = {2016}
    }
  • D. J. Strauss, A. Damian, E. González-Trejo, R. Hannemann, H. Mögele, and F. I. Corona-Strauss, "Neural Correlates of Listening Effort in a Multimodal Interactive Driving Environment," in HEAL - Hearing Across the Lifespan, 2016.
    [BibTeX]
    @inproceedings{straea2016,
      author = {Strauss, D. J. and Damian, A. and Gonz\'{a}lez-Trejo, E. and Hannemann, R. and M\"{o}gele, H. and Corona-Strauss, F. I.},
      title = {Neural Correlates of Listening Effort in a Multimodal Interactive Driving Environment},
      booktitle = {HEAL - Hearing Across the Lifespan},
      year = {2016}
    }

2015

  • Z. Mortezapouraghdam, L. Haab, F. I. Corona-Strauss, G. Steidl, and D. J. Strauss, "Assessment of Long-Term Habituation Correlates in Event-Related Potentials Using a von Mises Model," IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 23, iss. 3, pp. 363-373, 2015. doi:10.1109/tnsre.2014.2361614
    [BibTeX] [Abstract]
    In our preliminary work we were able to demonstrate habituation by analyzing attention correlates in single-trial sequences of auditory event-related potentials (ERPs). Despite different quantitative studies of instantaneous phase of ERPs in long-term habituation, there have been no former studies in generative process underlying the distribution of instantaneous phase information in the context of long-term habituation and its relation to attentional binding. For this means we used a von Mises model, representing the phase information over a set of single trial responses. Additionally we use a quantitative neurofunctional model to predict the dynamics of the instantaneous phase in single-trial ERP data during the long-term habituation. Measured habituation data is used to cross-validate the model's prediction. We conclude that the described method allows for an assessment of dynamic changes in the course of long-term habituation. The results also reinforce our neurofunctional multiscale model of long-term habituation and show the applicability of the described method for the experimental/clinical neurodiagnostic assessment of attentional binding.
    @Article{mortea2015,
      author    = {Mortezapouraghdam, Z. and Haab, L. and Corona-Strauss, F. I. and Steidl, G. and Strauss, D. J.},
      journal   = {{IEEE} Transactions on Neural Systems and Rehabilitation Engineering},
      title     = {Assessment of Long-Term Habituation Correlates in Event-Related Potentials Using a von Mises Model},
      year      = {2015},
      month     = {may},
      number    = {3},
      pages     = {363-373},
      volume    = {23},
      abstract  = {In our preliminary work we were able to demonstrate habituation by analyzing attention correlates in single-trial sequences of auditory event-related potentials (ERPs). Despite different quantitative studies of instantaneous phase of ERPs in long-term habituation, there have been no former studies in generative process underlying the distribution of instantaneous phase information in the context of long-term habituation and its relation to attentional binding. For this means we used a von Mises model, representing the phase information over a set of single trial responses. Additionally we use a quantitative neurofunctional model to predict the dynamics of the instantaneous phase in single-trial ERP data during the long-term habituation. Measured habituation data is used to cross-validate the model's prediction. We conclude that the described method allows for an assessment of dynamic changes in the course of long-term habituation. The results also reinforce our neurofunctional multiscale model of long-term habituation and show the applicability of the described method for the experimental/clinical neurodiagnostic assessment of attentional binding.},
      doi       = {10.1109/tnsre.2014.2361614},
      keywords  = {Auditory selective attention,Long-term habituation,Phase synchronization,Von mises distribution},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • C. Bernarding, D. J. Strauss, R. Hannemann, H. Seidler, and F. I. Corona-Strauss, "Objective extraction of dynamical listening effort profiles," in 2015 7th International IEEE/EMBS Conference on Neural Engineering (NER), 2015, pp. 1100-1103. doi:10.1109/ner.2015.7146820
    [BibTeX] [Abstract]
    In complex listening environments, people with hearing loss have an increased listening effort to achieve a similar speech understanding level as normal hearing people. However, a standardized method to estimate this listening effort does not exist. Recently, we have shown a possible way to determine listening effort objectively. This method is based on the phase distribution of the ongoing oscillatory EEG activity. The aim of the current study was to assess, whether such objective methods can also be used to extract dynamical listening effort profiles in persons with a moderate hearing loss. Hearing aids were fitted using a directional microphone (DM) configuration, a new binaurally coupled hearing aid technique (BHA) and a fitting using omnidirectional microphones (ODM). Furthermore, a temporal resolution of the measure was obtained to unveil underlying processes such as fatigue effects or a cessation to spend attentional effort. The results indicate that time-varying listening effort profiles related to effects like fatigue or a cessation to solve the auditory task can be detected by the proposed objective measures.
    @InProceedings{bernea2015,
      author    = {Bernarding, C. and Strauss, D. J. and Hannemann, R. and Seidler, H. and Corona-Strauss, F. I.},
      booktitle = {2015 7th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Objective extraction of dynamical listening effort profiles},
      year      = {2015},
      month     = {apr},
      pages     = {1100-1103},
      publisher = {{IEEE}},
      abstract  = {In complex listening environments, people with hearing loss have an increased listening effort to achieve a similar speech understanding level as normal hearing people. However, a standardized method to estimate this listening effort does not exist. Recently, we have shown a possible way to determine listening effort objectively. This method is based on the phase distribution of the ongoing oscillatory EEG activity. The aim of the current study was to assess, whether such objective methods can also be used to extract dynamical listening effort profiles in persons with a moderate hearing loss. Hearing aids were fitted using a directional microphone (DM) configuration, a new binaurally coupled hearing aid technique (BHA) and a fitting using omnidirectional microphones (ODM). Furthermore, a temporal resolution of the measure was obtained to unveil underlying processes such as fatigue effects or a cessation to spend attentional effort. The results indicate that time-varying listening effort profiles related to effects like fatigue or a cessation to solve the auditory task can be detected by the proposed objective measures.},
      doi       = {10.1109/ner.2015.7146820},
    }
  • A. Damian, F. I. Corona-Strauss, R. Hannemann, and D. J. Strauss, "Towards the assessment of listening effort in real life situations: Mobile EEG recordings in a multimodal driving situation," in 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015, pp. 8123-8126. doi:10.1109/embc.2015.7320279
    [BibTeX] [Abstract]
    The EEG estimation of listening effort has been proven to efficiently map subjectively perceived effort on an objective scale. However, it has mostly been performed in controlled audiometric laboratory environments. In this study, we investigated the feasibility of the EEG listening effort assessment in a multisensory demanding environment. For this purpose, two mobile EEG acquisition systems were used to extract the objective listening effort of the ongoing oscillatory activity (OLEosc) while driving. As an auditory paradigm was presented to trigger listening effort, the simulated driving scenario served as a competing task responding to different modalities. The OLEosc was compared with a subjective rating of the expended listening effort and the task performance. Furthermore, we considered time resolved listening effort profiles over the duration of the paradigm. The results showed that the practical assessment of listening effort in a multimodal real life setting is viable. The OLEosc could be extracted and followed the subjective listening effort. Moreover, the analysis of the dynamic listening effort profiles unveiled further information such as 'surrender effects', when the subjects ceased to solve the auditory task due to the intense multimodal load.
    @InProceedings{damiea2015,
      author    = {Damian, A. and Corona-Strauss, F. I. and Hannemann, R. and Strauss, D. J.},
      booktitle = {2015 37th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Towards the assessment of listening effort in real life situations: Mobile {EEG} recordings in a multimodal driving situation},
      year      = {2015},
      month     = {aug},
      pages     = {8123-8126},
      publisher = {{IEEE}},
      abstract  = {The EEG estimation of listening effort has been proven to efficiently map subjectively perceived effort on an objective scale. However, it has mostly been performed in controlled audiometric laboratory environments. In this study, we investigated the feasibility of the EEG listening effort assessment in a multisensory demanding environment. For this purpose, two mobile EEG acquisition systems were used to extract the objective listening effort of the ongoing oscillatory activity (OLEosc) while driving. As an auditory paradigm was presented to trigger listening effort, the simulated driving scenario served as a competing task responding to different modalities. The OLEosc was compared with a subjective rating of the expended listening effort and the task performance. Furthermore, we considered time resolved listening effort profiles over the duration of the paradigm. The results showed that the practical assessment of listening effort in a multimodal real life setting is viable. The OLEosc could be extracted and followed the subjective listening effort. Moreover, the analysis of the dynamic listening effort profiles unveiled further information such as 'surrender effects', when the subjects ceased to solve the auditory task due to the intense multimodal load.},
      doi       = {10.1109/embc.2015.7320279},
    }
  • E. González-Trejo, M. C. Kohl, A. Steinbach, H. Mögele, N. Pfleger, and D. J. Strauss, "Correlation between cortical inhibition and auditory stream segregation in a driving environment," in 2015 7th International IEEE/EMBS Conference on Neural Engineering (NER), 2015, pp. 747-750. doi:10.1109/ner.2015.7146731
    [BibTeX] [Abstract]
    Streams of information reach the brain in different modalities while driving (both from the vehicle user interface as well as the environment), each requiring a certain degree of attention from the driver. The driver should ideally be able to focus on the road ahead and not on secondary streams such as vehicle alerts, mobile phone, passengers or radio. However, the individual ability to selectively ignore distractions can have a direct influence on driving performance. Here, we use paired-chirp auditory late responses (ALRs) in order to assess long interval cortical inhibition (LICI) in healthy subjects, and compare it to the score in an auditory stream segregation task within a driving simulator. Results show significant correlation between LICI and task scores, suggesting that people with a higher/more effective cortical inhibition as measured by ALRs can ignore distracting streams easily, while people with less effective cortical inhibition find harder to concentrate on a single, more relevant stream. The fundamental results obtained suggest that cortical inhibition may be employed as a predictor of driving performance, useful for the design of auditory human-vehicle interfaces.
    @InProceedings{gonzea2015,
      author    = {Gonz\'{a}lez-Trejo, E. and Kohl, M. C. and Steinbach, A. and M\"{o}gele, H. and Pfleger, N. and Strauss, D. J.},
      booktitle = {2015 7th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Correlation between cortical inhibition and auditory stream segregation in a driving environment},
      year      = {2015},
      month     = {apr},
      pages     = {747-750},
      publisher = {{IEEE}},
      abstract  = {Streams of information reach the brain in different modalities while driving (both from the vehicle user interface as well as the environment), each requiring a certain degree of attention from the driver. The driver should ideally be able to focus on the road ahead and not on secondary streams such as vehicle alerts, mobile phone, passengers or radio. However, the individual ability to selectively ignore distractions can have a direct influence on driving performance. Here, we use paired-chirp auditory late responses (ALRs) in order to assess long interval cortical inhibition (LICI) in healthy subjects, and compare it to the score in an auditory stream segregation task within a driving simulator. Results show significant correlation between LICI and task scores, suggesting that people with a higher/more effective cortical inhibition as measured by ALRs can ignore distracting streams easily, while people with less effective cortical inhibition find harder to concentrate on a single, more relevant stream. The fundamental results obtained suggest that cortical inhibition may be employed as a predictor of driving performance, useful for the design of auditory human-vehicle interfaces.},
      doi       = {10.1109/ner.2015.7146731},
    }
  • I. Klauke, M. C. Kohl, R. Hannemann, U. Kornagel, D. J. Strauss, and F. I. Corona-Strauss, "Impact of monaural frequency compression on binaural fusion at the brainstem level," in 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015, pp. 1646-1649. doi:10.1109/embc.2015.7318691
    [BibTeX] [Abstract]
    A classical objective measure for binaural fusion at the brainstem level is the so-called $\beta$-wave of the binaural interaction component (BIC) in the auditory brainstem response (ABR). However, in some cases it appeared that a reliable detection of this component still remains a challenge. In this study, we investigate the wavelet phase synchronization stability (WPSS) of ABR data for the analysis of binaural fusion and compare it to the BIC. In particular, we examine the impact of monaural nonlinear frequency compression on binaural fusion. As the auditory system is tonotopically organized, an interaural frequency mismatch caused by monaural frequency compression could negatively effect binaural fusion. In this study, only few subjects showed a detectable $\beta$-wave and in most cases only for low ITDs. However, we present a novel objective measure for binaural fusion that outperforms the current state-of-the-art technique (BIC): the WPSS analysis showed a significant difference between the phase stability of the sum of the monaurally evoked responses and the phase stability of the binaurally evoked ABR. This difference could be an indicator for binaural fusion in the brainstem. Furthermore, we observed that monaural frequency compression could indeed effect binaural fusion, as the WPSS results for this condition vary strongly from the results obtained without frequency compression.
    @InProceedings{klauea2015,
      author    = {Klauke, I. and Kohl, M. C. and Hannemann, R. and Kornagel, U. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {2015 37th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Impact of monaural frequency compression on binaural fusion at the brainstem level},
      year      = {2015},
      month     = {aug},
      pages     = {1646-1649},
      publisher = {{IEEE}},
      abstract  = {A classical objective measure for binaural fusion at the brainstem level is the so-called $\beta$-wave of the binaural interaction component (BIC) in the auditory brainstem response (ABR). However, in some cases it appeared that a reliable detection of this component still remains a challenge. In this study, we investigate the wavelet phase synchronization stability (WPSS) of ABR data for the analysis of binaural fusion and compare it to the BIC. In particular, we examine the impact of monaural nonlinear frequency compression on binaural fusion. As the auditory system is tonotopically organized, an interaural frequency mismatch caused by monaural frequency compression could negatively effect binaural fusion. In this study, only few subjects showed a detectable $\beta$-wave and in most cases only for low ITDs. However, we present a novel objective measure for binaural fusion that outperforms the current state-of-the-art technique (BIC): the WPSS analysis showed a significant difference between the phase stability of the sum of the monaurally evoked responses and the phase stability of the binaurally evoked ABR. This difference could be an indicator for binaural fusion in the brainstem. Furthermore, we observed that monaural frequency compression could indeed effect binaural fusion, as the WPSS results for this condition vary strongly from the results obtained without frequency compression.},
      doi       = {10.1109/embc.2015.7318691},
    }
  • C. Lehser, R. Hannemann, F. I. Corona-Strauss, D. J. Strauss, L. Haab, B. Seidler-Fallböhmer, and H. Seidler, "Dysfunctional long term habituation to exogeneous tinnitus-matched sounds in patients with high tinnitus distress," in 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015, pp. 1967-1970. doi:10.1109/embc.2015.7318770
    [BibTeX] [Abstract]
    During the last years, the demand of accurate diagnostic tools for individualized tinnitus treatment gradually increased. Today several different psychometric instruments for the estimation of the patients degree of decompensation with clinical relevance have emerged. All of these tools are questionnaires for a subjective self-assessment and have deficits in comparability due to severe differences in their factor structure in the anamnesis. Those questionnaires thus they are only of limited value in the design of an individualized therapeutic approach. Objective diagnostic tools for the categorization of the patients' distress level are lacking in clinical routine. Scientific approaches yet demonstrated the feasibility of individual distress assessment by objective markers in the EEG. In this article we present the preliminary results of our study of a use of habituation correlates as objective indicator for the decompensation degree in high-distress tinnitus patients.
    @InProceedings{lehsea2015,
      author    = {Lehser, C. and Hannemann, R. and Corona-Strauss, F. I. and Strauss, D. J. and Haab, L. and Seidler-Fallb\"{o}hmer, B. and Seidler, H.},
      booktitle = {2015 37th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Dysfunctional long term habituation to exogeneous tinnitus-matched sounds in patients with high tinnitus distress},
      year      = {2015},
      month     = {aug},
      pages     = {1967-1970},
      publisher = {{IEEE}},
      abstract  = {During the last years, the demand of accurate diagnostic tools for individualized tinnitus treatment gradually increased. Today several different psychometric instruments for the estimation of the patients degree of decompensation with clinical relevance have emerged. All of these tools are questionnaires for a subjective self-assessment and have deficits in comparability due to severe differences in their factor structure in the anamnesis. Those questionnaires thus they are only of limited value in the design of an individualized therapeutic approach. Objective diagnostic tools for the categorization of the patients' distress level are lacking in clinical routine. Scientific approaches yet demonstrated the feasibility of individual distress assessment by objective markers in the EEG. In this article we present the preliminary results of our study of a use of habituation correlates as objective indicator for the decompensation degree in high-distress tinnitus patients.},
      doi       = {10.1109/embc.2015.7318770},
    }
  • Z. Mortezapouraghdam, L. Haab, K. Schwerdtfeger, and D. J. Strauss, "Relating auditory evoked responses to the laminar phase dynamics in rats using mutual information," in 2015 7th International IEEE/EMBS Conference on Neural Engineering (NER), 2015, pp. 952-955. doi:10.1109/ner.2015.7146783
    [BibTeX] [Abstract]
    This study aims to decrease the gap between invasive high-resolution data acquisition and non-invasive measurement in the animal model under auditory stimuli. We approach this problem by analyzing the degree of shared information between the phase of local field potentials (LFPs) of auditory cortices and the phase of auditory evoked responses (AER) at different frequency domains. It has been extensively illustrated in previous studies that the phase of evoked responses align reliably in presence of a repetitive stimulus. Yet this implies that changes in the instantaneous phase over a series of stimulus presentations must also be mirrored in the laminar activity. To estimate the impact of laminar specific activity on the AER dynamics over a series of acoustic stimulation, we employ an information theoretic approach (mutual information) for quantifying the relevant information encoded in the phase of laminar LFPs and AERs.
    @InProceedings{mortea2015b,
      author    = {Mortezapouraghdam, Z. and Haab, L. and Schwerdtfeger, K. and Strauss, D. J.},
      booktitle = {2015 7th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Relating auditory evoked responses to the laminar phase dynamics in rats using mutual information},
      year      = {2015},
      month     = {apr},
      pages     = {952-955},
      publisher = {{IEEE}},
      abstract  = {This study aims to decrease the gap between invasive high-resolution data acquisition and non-invasive measurement in the animal model under auditory stimuli. We approach this problem by analyzing the degree of shared information between the phase of local field potentials (LFPs) of auditory cortices and the phase of auditory evoked responses (AER) at different frequency domains. It has been extensively illustrated in previous studies that the phase of evoked responses align reliably in presence of a repetitive stimulus. Yet this implies that changes in the instantaneous phase over a series of stimulus presentations must also be mirrored in the laminar activity. To estimate the impact of laminar specific activity on the AER dynamics over a series of acoustic stimulation, we employ an information theoretic approach (mutual information) for quantifying the relevant information encoded in the phase of laminar LFPs and AERs.},
      doi       = {10.1109/ner.2015.7146783},
    }
  • N. Özgün, R. Bennewitz, and D. J. Strauss, "Relating Tribological Stimuli to Single-Trial Somatosensory Electroencephalographic Responses: A Pilot Study," in 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015, pp. 8115-8118. doi:10.1109/embc.2015.7320277
    [BibTeX] [Abstract]
    The present study deals with the extraction of neural correlates evoked by tactile stimulation of the human fingertip. A reciprocal sliding procedure was performed using a home-built tribometer while simultaneously electroencephalographic (EEG) data from the somatosensory cortex was recorded. The tactile stimuli were delivered by a sliding block with equidistant, perpendicular ridges. The experiments were designed and performed in a fully passive way to prevent attentional locked influences from the subjects. In order to improve the signal-to-noise ratio (SNR) of event related single-trials (ERPs), nonlocal means in addition to 2D-anisotropic denoising schemes based on tight Gabor frames were applied. This novel approach allowed for an easier extraction of ERP alternations. A negative correlation between the latency of the P100 component of the resulting brain responses and the intensity of the underlying lateral forces was found. These findings lead to the conclusion that an increasing stimulus intensity results in a decreasing latency of the brain responses.
    @InProceedings{oezgea15,
      author    = {\"{O}zg\"{u}n, N. and Bennewitz, R. and Strauss, D. J.},
      booktitle = {2015 37th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Relating Tribological Stimuli to Single-Trial Somatosensory Electroencephalographic Responses: A Pilot Study},
      year      = {2015},
      month     = {aug},
      pages     = {8115-8118},
      publisher = {{IEEE}},
      abstract  = {The present study deals with the extraction of neural correlates evoked by tactile stimulation of the human fingertip. A reciprocal sliding procedure was performed using a home-built tribometer while simultaneously electroencephalographic (EEG) data from the somatosensory cortex was recorded. The tactile stimuli were delivered by a sliding block with equidistant, perpendicular ridges. The experiments were designed and performed in a fully passive way to prevent attentional locked influences from the subjects. In order to improve the signal-to-noise ratio (SNR) of event related single-trials (ERPs), nonlocal means in addition to 2D-anisotropic denoising schemes based on tight Gabor frames were applied. This novel approach allowed for an easier extraction of ERP alternations. A negative correlation between the latency of the P100 component of the resulting brain responses and the intensity of the underlying lateral forces was found. These findings lead to the conclusion that an increasing stimulus intensity results in a decreasing latency of the brain responses.},
      doi       = {10.1109/embc.2015.7320277},
    }
  • A. E. Romero Santiago, K. Schwerdtfeger, J. Szczygielski, P. Flotho, J. K. Schubert, L. Haab, M. Hmila, and D. J. Strauss, "Motion reduction and multidimensional denoising in Voltage-sensitive Dye imaging," in 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015, pp. 6273-6276. doi:10.1109/embc.2015.7319826
    [BibTeX] [Abstract]
    Optical Imaging using Voltage-sensitive Dyes is characterized by low fractional changes in fluorescent light intensity upon the application of a stimulus, which leads to slight value differences between pixels on an in-general noisy image sequence. The application of an anisotropic diffusion filtering scheme, in order to contribute to the denoising of the optical images, is proposed as one option to improve its quality and for a better understanding of the physiological processes they represent. We apply an image registration approach to compensate for motion artifacts, such that we do not need to mount a fixed cranial chamber onto the skull. In this work, electrical stimulation to the tibial nerve in a rat model was used to register evoke potentials, imaging the somatosensory cortex of the animal, which was previously stained with the
    @InProceedings{romeea15,
      author    = {Romero Santiago, A. E. and Schwerdtfeger, K. and Szczygielski, J. and Flotho, P. and Schubert, J. K. and Haab, L. and Hmila, M. and Strauss, D. J.},
      booktitle = {2015 37th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Motion reduction and multidimensional denoising in Voltage-sensitive Dye imaging},
      year      = {2015},
      month     = {aug},
      pages     = {6273-6276},
      publisher = {{IEEE}},
      abstract  = {Optical Imaging using Voltage-sensitive Dyes is characterized by low fractional changes in fluorescent light intensity upon the application of a stimulus, which leads to slight value differences between pixels on an in-general noisy image sequence. The application of an anisotropic diffusion filtering scheme, in order to contribute to the denoising of the optical images, is proposed as one option to improve its quality and for a better understanding of the physiological processes they represent. We apply an image registration approach to compensate for motion artifacts, such that we do not need to mount a fixed cranial chamber onto the skull. In this work, electrical stimulation to the tibial nerve in a rat model was used to register evoke potentials, imaging the somatosensory cortex of the animal, which was previously stained with the},
      doi       = {10.1109/embc.2015.7319826},
    }
  • N. Salafzoon, D. J. Strauss, N. G. Hatsopoulos, and K. Takahashi, "Dynamic interlaminar and thalamocortical interaction supported by top-down beta rhythms," in 2015 7th International IEEE/EMBS Conference on Neural Engineering (NER), 2015, pp. 382-385. doi:10.1109/ner.2015.7146639
    [BibTeX] [Abstract]
    The neocortex, as a great majority of the cerebral cortex, conceals multiple bands of oscillations recorded in local field potentials (LFPs), which are associated with different neural circuits and their corresponding brain functions. Not only are the complex neural connections in this area significant factors in the emergence of the cortical oscillations, but the inputs from the thalamus to the cortex along with cortical projections to dorsal thalamic nuclei and to the thalamic reticular nucleus as a part of the ventral nuclei as well. These cortical oscillations are related to sensory processing, memory, cognition, and motor control. Here, we developed a functional simulation model of the basic thalamocortical - corticothalamic loop architecture with detailed cortical laminar structure and a diverse set of neuron types. Our model generates prominent $\beta$ oscillations, and demonstrates the role of the time-varying bottom up inputs in the dynamics of $\beta$ oscillation in different layers of the cortex. Through excitatory top-down $\beta$ signals, which were strongly modulated based on frontal attentional inputs, two states were also modeled: Attended and Non-Attended.
    @InProceedings{salaea2015,
      author    = {Salafzoon, N. and Strauss, D. J. and Hatsopoulos, N.G. and Takahashi, K.},
      booktitle = {2015 7th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Dynamic interlaminar and thalamocortical interaction supported by top-down beta rhythms},
      year      = {2015},
      month     = {apr},
      pages     = {382-385},
      publisher = {{IEEE}},
      abstract  = {The neocortex, as a great majority of the cerebral cortex, conceals multiple bands of oscillations recorded in local field potentials (LFPs), which are associated with different neural circuits and their corresponding brain functions. Not only are the complex neural connections in this area significant factors in the emergence of the cortical oscillations, but the inputs from the thalamus to the cortex along with cortical projections to dorsal thalamic nuclei and to the thalamic reticular nucleus as a part of the ventral nuclei as well. These cortical oscillations are related to sensory processing, memory, cognition, and motor control. Here, we developed a functional simulation model of the basic thalamocortical - corticothalamic loop architecture with detailed cortical laminar structure and a diverse set of neuron types. Our model generates prominent $\beta$ oscillations, and demonstrates the role of the time-varying bottom up inputs in the dynamics of $\beta$ oscillation in different layers of the cortex. Through excitatory top-down $\beta$ signals, which were strongly modulated based on frontal attentional inputs, two states were also modeled: Attended and Non-Attended.},
      doi       = {10.1109/ner.2015.7146639},
    }
  • P. J. Schäfer, M. Serman, M. Arnold, F. I. Corona-Strauss, D. J. Strauss, B. Seidler-Fallböhmer, and H. Seidler, "Evaluation of an objective listening effort measure in a selective, multi-speaker listening task using different hearing aid settings," in 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015, pp. 4647-4650. doi:10.1109/embc.2015.7319430
    [BibTeX] [Abstract]
    Speaker recognition in a multi-speaker environment is a complex listening task that requires effort to be solved. Especially people with hearing loss show an increased listening effort in demanding listening situations compared to normal hearing people. However, a standardized method to quantify listening effort does not exist yet. Recently we have shown a possible way to determine listening effort objectively. The aim of this study was to validate the proposed objective measure in a challenging, true-to-life listening situation, and to get an insight on the influence of different hearing aid (HA) settings on the listening effort using the proposed measure. To achieve this we investigated the influence of four different HA settings and two different listening task difficulties (LTD) on the listening effort of people with hearing loss in a selective, real-speech listening task. HA setting A, B and C all had an adaptive compression with static characteristic, but differed in the gain and compression settings (more and less gain and more and less linear). Setting D had an adaptive compression whose characteristic was situation-dependent. To quantify the listening effort the ongoing oscillatory EEG activity was recorded as the basis to calculate the objective measure (OLEosc). By way of comparison a subjective listening effort score was determined on an individual basis (SLEscr). The results show that the OLEosc maps the SLEscr well in every of the tested conditions. Furthermore, the results also suggest that OLEosc might be more sensitive to small variances in listening effort than the employed subjective rating scale.
    @InProceedings{schaea2015,
      author    = {Sch\"{a}fer, P. J. and Serman, M. and Arnold, M. and Corona-Strauss, F. I. and Strauss, D. J. and Seidler-Fallb\"{o}hmer, B. and Seidler, H.},
      booktitle = {2015 37th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society ({EMBC})},
      title     = {Evaluation of an objective listening effort measure in a selective, multi-speaker listening task using different hearing aid settings},
      year      = {2015},
      month     = {aug},
      pages     = {4647-4650},
      publisher = {{IEEE}},
      abstract  = {Speaker recognition in a multi-speaker environment is a complex listening task that requires effort to be solved. Especially people with hearing loss show an increased listening effort in demanding listening situations compared to normal hearing people. However, a standardized method to quantify listening effort does not exist yet. Recently we have shown a possible way to determine listening effort objectively. The aim of this study was to validate the proposed objective measure in a challenging, true-to-life listening situation, and to get an insight on the influence of different hearing aid (HA) settings on the listening effort using the proposed measure. To achieve this we investigated the influence of four different HA settings and two different listening task difficulties (LTD) on the listening effort of people with hearing loss in a selective, real-speech listening task. HA setting A, B and C all had an adaptive compression with static characteristic, but differed in the gain and compression settings (more and less gain and more and less linear). Setting D had an adaptive compression whose characteristic was situation-dependent. To quantify the listening effort the ongoing oscillatory EEG activity was recorded as the basis to calculate the objective measure (OLEosc). By way of comparison a subjective listening effort score was determined on an individual basis (SLEscr). The results show that the OLEosc maps the SLEscr well in every of the tested conditions. Furthermore, the results also suggest that OLEosc might be more sensitive to small variances in listening effort than the employed subjective rating scale.},
      doi       = {10.1109/embc.2015.7319430},
    }
  • E. Schebsdat, F. I. Corona-Strauss, H. Hessel, H. Seidler, A. Bellagnech, L. Rusczyk, O. Müller, and D. J. Strauss, "Binaural Interaction in Unilateral Cochlear Implant Users: Neural Correlates in Free-Field Single Trial Responses," in Conf Proc IEEE Eng Med Biol Soc, 2015.
    [BibTeX]
    @inproceedings{scheea2015,
      author = {Schebsdat, E. and Corona-Strauss, F. I. and Hessel, H. and Seidler, H. and Bellagnech, A. and Rusczyk, L. and M\"{u}ller, O. and Strauss, D. J.},
      title = {Binaural Interaction in Unilateral Cochlear Implant Users: Neural Correlates in Free-Field Single Trial Responses},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      year = {2015}
    }

2014

  • J. K. Schubert, E. González-Trejo, M. Retz, M. Roesler, F. I. Corona-Strauss, G. Steidl, T. Teuber, and D. J. Strauss, "Dysfunctional cortical inhibition in adult ADHD: Neural correlates in auditory event-related potentials," Journal of Neuroscience Methods, vol. 235, pp. 181-188, 2014. doi:10.1016/j.jneumeth.2014.06.025
    [BibTeX] [Abstract]
    In recent times, the relevance of an accurate diagnosis of attention-deficit/hyperactivity disorder (ADHD) in adults has been the focus of several studies. No longer considered a pathology exclusive to children and adolescents, and taking into account its social implications, developing enhanced support tools for the current diagnostic procedure becomes a priority. Here we present a method for the objective assessment of ADHD in adults using chirp-evoked, paired auditory late responses (ALRs) combined with a two-dimensional ALR denoising scheme to extract correlates of intracortical inhibition. Our method allows for an effective single-sweep denoising, thus requiring less trials to obtain recognizable physiological features, useful as pointers of cortical impairment. Results allow an optimized diagnosis, reduction of data loss and acquisition time; moreover, they do not account exclusively for critical elements within clinical evaluations, but also allow studying the pathophysiology of the condition by providing objective information regarding impaired cortical functions.
    @Article{schuea2014,
      author    = {Schubert, J. K. and Gonz\'{a}lez-Trejo, E. and Retz, M. and Roesler, M. and Corona-Strauss, F. I. and Steidl, G. and Teuber, T. and Strauss, D. J.},
      journal   = {Journal of Neuroscience Methods},
      title     = {Dysfunctional cortical inhibition in adult {ADHD}: Neural correlates in auditory event-related potentials},
      year      = {2014},
      month     = {sep},
      pages     = {181-188},
      volume    = {235},
      abstract  = {In recent times, the relevance of an accurate diagnosis of attention-deficit/hyperactivity disorder (ADHD) in adults has been the focus of several studies. No longer considered a pathology exclusive to children and adolescents, and taking into account its social implications, developing enhanced support tools for the current diagnostic procedure becomes a priority. Here we present a method for the objective assessment of ADHD in adults using chirp-evoked, paired auditory late responses (ALRs) combined with a two-dimensional ALR denoising scheme to extract correlates of intracortical inhibition. Our method allows for an effective single-sweep denoising, thus requiring less trials to obtain recognizable physiological features, useful as pointers of cortical impairment. Results allow an optimized diagnosis, reduction of data loss and acquisition time; moreover, they do not account exclusively for critical elements within clinical evaluations, but also allow studying the pathophysiology of the condition by providing objective information regarding impaired cortical functions.},
      doi       = {10.1016/j.jneumeth.2014.06.025},
      keywords  = {Attention deficit,Denoising,Event-related potentials,Non-local means},
      publisher = {Elsevier {BV}},
    }
  • C. Bernarding, D. J. Strauss, R. Hannemann, H. Seidler, and F. I. Corona-Strauss, "Objective assessment of listening effort in the oscillatory EEG: Comparison of different hearing aid configurations," in 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014, pp. 2653-2656. doi:10.1109/embc.2014.6944168
    [BibTeX] [Abstract]
    An objective estimate of listening effort could support the hearing aid fitting procedure. Most of the digital hearing aids have already hearing aid settings which are supposed to reduce the listening effort, but the effects of these settings on the individual's listening effort remain unclear. In this study, we propose an objective estimate of listening effort using electroencephalographic data. The new method is based on the phase distribution of the ongoing oscillatory EEG activity. We hypothesize that for a non-effortful listening environment the phase is rather uniformly distributed on the unit circle than for a demanding condition. To prove if the phase is uniformly distributed around the unit circle, the Rayleigh Test was applied to the phase of the EEG. This method was tested in 14 hearing impaired subjects (moderate hearing loss, 65.64 ±7.93 yrs, 7 female). The tested hearing aid settings were a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off as well as a setting using omnidirectional microphones. Noise embedded sentences (Oldenburg Sentence Test, OlSa) were used as test materials. The task of the subject was to repeat each sentence. The results indicate that the objective estimate of listening effort maps the subjectively rated effort and for a listening situation like the presented one, the strong setting of the directional microphone requires the smallest effort.
    @InProceedings{bernea2014,
      author    = {Bernarding, C. and Strauss, D. J. and Hannemann, R. and Seidler, H. and Corona-Strauss, F. I.},
      booktitle = {2014 36th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society},
      title     = {Objective assessment of listening effort in the oscillatory {EEG}: Comparison of different hearing aid configurations},
      year      = {2014},
      month     = {aug},
      pages     = {2653-2656},
      publisher = {{IEEE}},
      volume    = {2014:1},
      abstract  = {An objective estimate of listening effort could support the hearing aid fitting procedure. Most of the digital hearing aids have already hearing aid settings which are supposed to reduce the listening effort, but the effects of these settings on the individual's listening effort remain unclear. In this study, we propose an objective estimate of listening effort using electroencephalographic data. The new method is based on the phase distribution of the ongoing oscillatory EEG activity. We hypothesize that for a non-effortful listening environment the phase is rather uniformly distributed on the unit circle than for a demanding condition. To prove if the phase is uniformly distributed around the unit circle, the Rayleigh Test was applied to the phase of the EEG. This method was tested in 14 hearing impaired subjects (moderate hearing loss, 65.64 ±7.93 yrs, 7 female). The tested hearing aid settings were a directional microphone combined with a noise reduction algorithm in a medium and a strong setting, the noise reduction setting turned off as well as a setting using omnidirectional microphones. Noise embedded sentences (Oldenburg Sentence Test, OlSa) were used as test materials. The task of the subject was to repeat each sentence. The results indicate that the objective estimate of listening effort maps the subjectively rated effort and for a listening situation like the presented one, the strong setting of the directional microphone requires the smallest effort.},
      doi       = {10.1109/embc.2014.6944168},
    }
  • L. Haab, Z. Mortezapouraghdam, and D. J. Strauss, "Modeling prediction of a generalized habituation deficit in decompensated tinnitus sufferers," in 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014, pp. 5691-5694. doi:10.1109/embc.2014.6944919
    [BibTeX] [Abstract]
    The pathologic auditory sensation in decompensated tinnitus patients is accompanied by the inability to habituate even temporary to this sound. This disability might originate from simultaneous activation of brain areas for the appraisal of the stimulus valence as, e.g., the limbic system. This coactivation of limbic areas is likely to modulate the degree and persistence of selective attention assigned to the tinnitus stream, which in turn could also explain interindividual differences in tinnitus loudness perception. Preliminary studies demonstrate that the amount of allocated attention and the habituation deficit can be mapped to changes in auditory late evoked responses (ALRs). Utilizing a numerical model for the simulation of ALRs we were able to predict a general habituation behavior in two patient groups with different degrees of tinnitus severity. Evaluating the instantaneous phase of simulated and measured ALRs by its von Mises concentration parameter, we verify a habituation deficit relative to the degree of decompensation and thus provide additional support for our neurofunctional model of limbic influences on neural processing of sensory information.
    @InProceedings{haabea2014,
      author    = {Haab, L. and Mortezapouraghdam, Z. and Strauss, D. J.},
      booktitle = {2014 36th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society},
      title     = {Modeling prediction of a generalized habituation deficit in decompensated tinnitus sufferers},
      year      = {2014},
      month     = {aug},
      pages     = {5691-5694},
      publisher = {{IEEE}},
      volume    = {2014:1},
      abstract  = {The pathologic auditory sensation in decompensated tinnitus patients is accompanied by the inability to habituate even temporary to this sound. This disability might originate from simultaneous activation of brain areas for the appraisal of the stimulus valence as, e.g., the limbic system. This coactivation of limbic areas is likely to modulate the degree and persistence of selective attention assigned to the tinnitus stream, which in turn could also explain interindividual differences in tinnitus loudness perception. Preliminary studies demonstrate that the amount of allocated attention and the habituation deficit can be mapped to changes in auditory late evoked responses (ALRs). Utilizing a numerical model for the simulation of ALRs we were able to predict a general habituation behavior in two patient groups with different degrees of tinnitus severity. Evaluating the instantaneous phase of simulated and measured ALRs by its von Mises concentration parameter, we verify a habituation deficit relative to the degree of decompensation and thus provide additional support for our neurofunctional model of limbic influences on neural processing of sensory information.},
      doi       = {10.1109/embc.2014.6944919},
    }
  • Z. Mortezapouraghdam, L. Haab, G. Steidl, and D. J. Strauss, "Detection of change points in phase data: A Bayesian analysis of habituation processes," in 2014 36th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2014, pp. 1014-1017. doi:10.1109/embc.2014.6943765
    [BibTeX] [Abstract]
    Given a time series of data points, as obtained in biosignal monitoring, the change point problem poses the question of identifying times of sudden variations in the parameters of the underlying data distribution. We propose a method for extracting a discrete set of change points from directional data. Our method is based on a combination of the Bayesian change point model (CPM) and the Viterbi algorithm. We apply our method to the instantaneous phase information of single-trial auditory event-related potentials (ERPs) in a long term habituation paradigm. We have seen in previous studies that the phase information enters a phase-locked mode with respect to the repetition of a stimulus in the state of focused attention. With adaptation to an insignificant stimulus, attention tends to trail away (long-term habituation), characterized by changes in the phase signature, becoming more diffuse across trials. We demonstrate that the proposed method is suitable for detecting the effects of long-term habituation on phase information in our experimental setting.
    @InProceedings{mortea2014b,
      author    = {Mortezapouraghdam, Z. and Haab, L. and Steidl, G. and Strauss, D. J.},
      booktitle = {2014 36th Annual International Conference of the {IEEE} Engineering in Medicine and Biology Society},
      title     = {Detection of change points in phase data: A Bayesian analysis of habituation processes},
      year      = {2014},
      month     = {aug},
      pages     = {1014-1017},
      publisher = {{IEEE}},
      volume    = {2014:1},
      abstract  = {Given a time series of data points, as obtained in biosignal monitoring, the change point problem poses the question of identifying times of sudden variations in the parameters of the underlying data distribution. We propose a method for extracting a discrete set of change points from directional data. Our method is based on a combination of the Bayesian change point model (CPM) and the Viterbi algorithm. We apply our method to the instantaneous phase information of single-trial auditory event-related potentials (ERPs) in a long term habituation paradigm. We have seen in previous studies that the phase information enters a phase-locked mode with respect to the repetition of a stimulus in the state of focused attention. With adaptation to an insignificant stimulus, attention tends to trail away (long-term habituation), characterized by changes in the phase signature, becoming more diffuse across trials. We demonstrate that the proposed method is suitable for detecting the effects of long-term habituation on phase information in our experimental setting.},
      doi       = {10.1109/embc.2014.6943765},
    }

2013

  • M. Busse, D. Stevens, M. Vukelic, A. Kraegeloh, C. Cavelius, E. Arzt, and D. J. Strauss, "Estimating the Modulatory Effects of Nanoparticles on Neuronal Circuits Using Computational Upscaling," International Journal of Nanomedicine, vol. 8, pp. 3559-3572, 2013. doi:10.2147/ijn.s43663
    [BibTeX] [Abstract]
    Background: Beside the promising application potential of nanotechnologies in engineering, the use of nanomaterials in medicine is growing. New therapies employing innovative nanocarrier systems to increase specificity and efficacy of drug delivery schemes are already in clinical trials. However the influence of the nanoparticles themselves is still unknown in medical applications, especially for complex interactions in neural systems. The aim of this study was to investigate in vitro effects of coated silver nanoparticles (cAgNP) on the excitability of single neuronal cells and to integrate those findings into an in silico model to predict possible effects on neuronal circuits. Methods: We first performed patch clamp measurements to investigate the effects of nanosized silver particles, surrounded by an organic coating, on excitability of single cells. We then determined which parameters were altered by exposure to those nanoparticles using the Hodgkin-Huxley model of the sodium current. As a third step, we integrated those findings into a well-defined neuronal circuit of thalamocortical interactions to predict possible changes in network signaling due to the applied cAgNP, in silico. Results: We observed rapid suppression of sodium currents after exposure to cAgNP in our in vitro recordings. In numerical simulations of sodium currents we identified the parameters likely affected by cAgNP. We then examined the effects of such changes on the activity of networks. In silico network modeling indicated effects of local cAgNP application on firing patterns in all neurons in the circuit. Conclusion: Our sodium current simulation shows that suppression of sodium currents by cAgNP results primarily by a reduction in the amplitude of the current. The network simulation shows that locally cAgNP-induced changes result in changes in network activity in the entire network, indicating that local application of cAgNP may influence the activity throughout the network.
    @Article{bussea2013,
      author    = {Busse, M. and Stevens, D. and Vukelic, M. and Kraegeloh, A. and Cavelius, C. and Arzt, E. and Strauss, D. J.},
      journal   = {International Journal of Nanomedicine},
      title     = {Estimating the Modulatory Effects of Nanoparticles on Neuronal Circuits Using Computational Upscaling},
      year      = {2013},
      month     = {sep},
      pages     = {3559-3572},
      volume    = {8},
      abstract  = {Background: Beside the promising application potential of nanotechnologies in engineering, the use of nanomaterials in medicine is growing. New therapies employing innovative nanocarrier systems to increase specificity and efficacy of drug delivery schemes are already in clinical trials. However the influence of the nanoparticles themselves is still unknown in medical applications, especially for complex interactions in neural systems. The aim of this study was to investigate in vitro effects of coated silver nanoparticles (cAgNP) on the excitability of single neuronal cells and to integrate those findings into an in silico model to predict possible effects on neuronal circuits. Methods: We first performed patch clamp measurements to investigate the effects of nanosized silver particles, surrounded by an organic coating, on excitability of single cells. We then determined which parameters were altered by exposure to those nanoparticles using the Hodgkin-Huxley model of the sodium current. As a third step, we integrated those findings into a well-defined neuronal circuit of thalamocortical interactions to predict possible changes in network signaling due to the applied cAgNP, in silico. Results: We observed rapid suppression of sodium currents after exposure to cAgNP in our in vitro recordings. In numerical simulations of sodium currents we identified the parameters likely affected by cAgNP. We then examined the effects of such changes on the activity of networks. In silico network modeling indicated effects of local cAgNP application on firing patterns in all neurons in the circuit. Conclusion: Our sodium current simulation shows that suppression of sodium currents by cAgNP results primarily by a reduction in the amplitude of the current. The network simulation shows that locally cAgNP-induced changes result in changes in network activity in the entire network, indicating that local application of cAgNP may influence the activity throughout the network.},
      doi       = {10.2147/ijn.s43663},
      keywords  = {Coated silver nanoparticles,Llin{\'{a}}s model,Modeling,Nanocarriers,Neuromodulatory effect,Neuronal circuit model,Nonviral vectors,Patch clamp recordings},
      publisher = {Informa {UK} Limited},
    }
  • C. Bernarding, D. J. Strauss, R. Hannemann, H. Seidler, and F. I. Corona-Strauss, "Neural correlates of listening effort related factors: Influence of age and hearing impairment," Brain Research Bulletin, vol. 91, pp. 21-30, 2013. doi:10.1016/j.brainresbull.2012.11.005
    [BibTeX] [Abstract]
    In the last years, there has been a rising interest to find an objective method to estimate listening effort. Previously, we have shown that the wavelet phase synchronization stability (WPSS), gained from the instantaneous phase of auditory late responses (ALRs), could serve as a feasible measure for listening effort related factors.In the current study, we examined if the WPSS reflects the listening effort in young as well as middle-aged subjects and in persons with a different degree of hearing loss. To evoke ALR sequences, we generated syllabic paradigms with a different level of difficulty to evoke ALR sequences. We expected, due to the varying task demand, that the subjects require a measurable difference in the amount of effort to solve the paradigms. Additionally, a possible age and/or hearing loss related effect on the neural correlates of listening effort was investigated.The results indicate, that WPSS reflects the listening effort related factors needed to solve an auditory task. A further finding was that the reaction time data and the N1 wave amplitude information hardly yield any correlate of the invested listening effort. In addition, we noticed an age as well as hearing sensitivity related effect on the listening effort.
    @Article{bernea2013,
      author    = {Bernarding, C. and Strauss, D. J. and Hannemann, R. and Seidler, H. and Corona-Strauss, F. I.},
      journal   = {Brain Research Bulletin},
      title     = {Neural correlates of listening effort related factors: Influence of age and hearing impairment},
      year      = {2013},
      month     = {feb},
      pages     = {21-30},
      volume    = {91},
      abstract  = {In the last years, there has been a rising interest to find an objective method to estimate listening effort. Previously, we have shown that the wavelet phase synchronization stability (WPSS), gained from the instantaneous phase of auditory late responses (ALRs), could serve as a feasible measure for listening effort related factors.In the current study, we examined if the WPSS reflects the listening effort in young as well as middle-aged subjects and in persons with a different degree of hearing loss. To evoke ALR sequences, we generated syllabic paradigms with a different level of difficulty to evoke ALR sequences. We expected, due to the varying task demand, that the subjects require a measurable difference in the amount of effort to solve the paradigms. Additionally, a possible age and/or hearing loss related effect on the neural correlates of listening effort was investigated.The results indicate, that WPSS reflects the listening effort related factors needed to solve an auditory task. A further finding was that the reaction time data and the N1 wave amplitude information hardly yield any correlate of the invested listening effort. In addition, we noticed an age as well as hearing sensitivity related effect on the listening effort.},
      doi       = {10.1016/j.brainresbull.2012.11.005},
      keywords  = {Auditory late responses,Hearing impairment,Listening effort},
      publisher = {Elsevier {BV}},
    }
  • D. J. Strauss, T. Teuber, G. Steidl, and F. I. Corona-Strauss, "Exploiting the Self-Similarity in ERP Images by Nonlocal Means for Single-Trial Denoising," IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 21, iss. 4, pp. 576-583, 2013. doi:10.1109/tnsre.2012.2220568
    [BibTeX] [Abstract]
    Event related potentials (ERPs) represent a noninvasive and widely available means to analyze neural correlates of sensory and cognitive processing. Recent developments in neural and cognitive engineering proposed completely new application fields of this well-established measurement technique when using an advanced single-trial processing. We have recently shown that 2-D diffusion filtering methods from image processing can be used for the denoising of ERP single-trials in matrix representations, also called ERP images. In contrast to conventional 1-D transient ERP denoising techniques, the 2-D restoration of ERP images allows for an integration of regularities over multiple stimulations into the denoising process. Advanced anisotropic image restoration methods may require directional information for the ERP denoising process. This is especially true if there is a lack of a priori knowledge about possible traces in ERP images. However due to the use of event related experimental paradigms, ERP images are characterized by a high degree of self-similarity over the individual trials. In this paper, we propose the simple and easy to apply nonlocal means method for ERP image denoising in order to exploit this self-similarity rather than focusing on the edge-based extraction of directional information. Using measured and simulated ERP data, we compare our method to conventional approaches in ERP denoising. It is concluded that the self-similarity in ERP images can be exploited for single-trial ERP denoising by the proposed approach. This method might be promising for a variety of evoked and event-related potential applications, including nonstationary paradigms such as changing exogeneous stimulus characteristics or endogenous states during the experiment. As presented, the proposed approach is for the a posteriori denoising of single-trial sequences.
    @Article{straea2013,
      author    = {Strauss, D. J. and Teuber, T. and Steidl, G. and Corona-Strauss, F. I.},
      journal   = {{IEEE} Transactions on Neural Systems and Rehabilitation Engineering},
      title     = {Exploiting the Self-Similarity in {ERP} Images by Nonlocal Means for Single-Trial Denoising},
      year      = {2013},
      month     = {jul},
      number    = {4},
      pages     = {576-583},
      volume    = {21},
      abstract  = {Event related potentials (ERPs) represent a noninvasive and widely available means to analyze neural correlates of sensory and cognitive processing. Recent developments in neural and cognitive engineering proposed completely new application fields of this well-established measurement technique when using an advanced single-trial processing. We have recently shown that 2-D diffusion filtering methods from image processing can be used for the denoising of ERP single-trials in matrix representations, also called ERP images. In contrast to conventional 1-D transient ERP denoising techniques, the 2-D restoration of ERP images allows for an integration of regularities over multiple stimulations into the denoising process. Advanced anisotropic image restoration methods may require directional information for the ERP denoising process. This is especially true if there is a lack of a priori knowledge about possible traces in ERP images. However due to the use of event related experimental paradigms, ERP images are characterized by a high degree of self-similarity over the individual trials. In this paper, we propose the simple and easy to apply nonlocal means method for ERP image denoising in order to exploit this self-similarity rather than focusing on the edge-based extraction of directional information. Using measured and simulated ERP data, we compare our method to conventional approaches in ERP denoising. It is concluded that the self-similarity in ERP images can be exploited for single-trial ERP denoising by the proposed approach. This method might be promising for a variety of evoked and event-related potential applications, including nonstationary paradigms such as changing exogeneous stimulus characteristics or endogenous states during the experiment. As presented, the proposed approach is for the a posteriori denoising of single-trial sequences.},
      doi       = {10.1109/tnsre.2012.2220568},
      keywords  = {Denoising,event-related potential images,event-related potentials,nonlocal image processing,nonlocal means,single-sweep,single-trial},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • C. Bernarding, R. Hannemann, D. Herrmann, D. J. Strauss, and F. I. Corona-Strauss, "Extraction of listening effort correlates in the oscillatory EEG activity: Investigation of different hearing aid configurations," in 2013 6th International IEEE/EMBS Conference on Neural Engineering (NER), 2013, pp. 1258-1261. doi:10.1109/ner.2013.6696169
    [BibTeX] [Abstract]
    A generally accepted objective measure for listening effort in hearing aid fitting procedures is still missing. Thus, the focus of our research is the extraction of possible neural correlates of listening effort by using electroencephalographic data. Such an objective measure could optimize the hearing aid fitting procedures by reducing the listening effort in hearing aid wearers. In the current study, we tested different hearing aid configurations in 15 normal hearing persons. For this, we created a realistic listening situation using standardized sentences embedded in multitalker babble noise at a fixed signal to noise ratio. The main objectives were (i) to extract possible neural correlates of listening effort using the previously proposed angular entropy measure; (ii) to find the respective electrode locations and scales (frequencies) which best represent the subjectively rated listening effort. In order to decompose the multiway data (electrode channel × number of sentences × scales) the parallel factor analysis (PARAFAC) was applied to the ANOVA F-test values. The results indicate that the refined angular entropy could serve as a possible correlate of listening effort in frontal electrode locations in the frequency range of the EEG theta band. Anyway further research is necessary to validate these findings.
    @InProceedings{bernea2013b,
      author    = {Bernarding, C. and Hannemann, R. and Herrmann, D. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {2013 6th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Extraction of listening effort correlates in the oscillatory {EEG} activity: Investigation of different hearing aid configurations},
      year      = {2013},
      month     = {nov},
      pages     = {1258-1261},
      publisher = {{IEEE}},
      abstract  = {A generally accepted objective measure for listening effort in hearing aid fitting procedures is still missing. Thus, the focus of our research is the extraction of possible neural correlates of listening effort by using electroencephalographic data. Such an objective measure could optimize the hearing aid fitting procedures by reducing the listening effort in hearing aid wearers. In the current study, we tested different hearing aid configurations in 15 normal hearing persons. For this, we created a realistic listening situation using standardized sentences embedded in multitalker babble noise at a fixed signal to noise ratio. The main objectives were (i) to extract possible neural correlates of listening effort using the previously proposed angular entropy measure; (ii) to find the respective electrode locations and scales (frequencies) which best represent the subjectively rated listening effort. In order to decompose the multiway data (electrode channel × number of sentences × scales) the parallel factor analysis (PARAFAC) was applied to the ANOVA F-test values. The results indicate that the refined angular entropy could serve as a possible correlate of listening effort in frontal electrode locations in the frequency range of the EEG theta band. Anyway further research is necessary to validate these findings.},
      doi       = {10.1109/ner.2013.6696169},
    }
  • E. González-Trejo, D. Herrmann, M. C. Kohl, F. I. Corona-Strauss, and D. J. Strauss, "Paired Chirp Evoked Cortical Inhibition and its Behavioral Correlates in a Speech Intelligibility Task," in 2013 6th International IEEE/EMBS Conference on Neural Engineering (NER), 2013, pp. 1350-1353. doi:10.1109/ner.2013.6696192
    [BibTeX] [Abstract]
    Successful auditory stream segregation depends on correctly inhibiting irrelevant stimuli being perceived in parallel with relevant information. Here, we analyze the behavioral correlates of inhibitory processing in healthy subjects, by first calculating the percentage of inhibition elicited through a paired-chirp auditory stimulation paradigm and then analyzing its correlation to the score in a speech intelligibility task. Analysis of cortical inhibition was made both in amplitude and phase, focusing on the N1-P2 complex. Significant inhibition between the condition and the test chirp in both of the inter stimulus intervals (ISIs) used and both N1 and P2 waves was observed. Inhibition in phase synchronization stability (PSS) showed a positive correlation to scores obtained in the task for all given modalities of the study, while amplitude analysis showed a correlation for the N1 wave with 500 ms ISI only. It was shown that the PSS analysis provides a more reliable representation of cortical inhibition, able to correlate to the attentional task. It is concluded that the given paradigm allows to assess inhibitory processing, vital to the allocation of attention.
    @InProceedings{gonzea2013,
      author    = {Gonz\'{a}lez-Trejo, E. and Herrmann, D. and Kohl, M. C. and Corona-Strauss, F. I. and Strauss, D. J.},
      booktitle = {2013 6th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Paired Chirp Evoked Cortical Inhibition and its Behavioral Correlates in a Speech Intelligibility Task},
      year      = {2013},
      month     = {nov},
      pages     = {1350-1353},
      publisher = {{IEEE}},
      abstract  = {Successful auditory stream segregation depends on correctly inhibiting irrelevant stimuli being perceived in parallel with relevant information. Here, we analyze the behavioral correlates of inhibitory processing in healthy subjects, by first calculating the percentage of inhibition elicited through a paired-chirp auditory stimulation paradigm and then analyzing its correlation to the score in a speech intelligibility task. Analysis of cortical inhibition was made both in amplitude and phase, focusing on the N1-P2 complex. Significant inhibition between the condition and the test chirp in both of the inter stimulus intervals (ISIs) used and both N1 and P2 waves was observed. Inhibition in phase synchronization stability (PSS) showed a positive correlation to scores obtained in the task for all given modalities of the study, while amplitude analysis showed a correlation for the N1 wave with 500 ms ISI only. It was shown that the PSS analysis provides a more reliable representation of cortical inhibition, able to correlate to the attentional task. It is concluded that the given paradigm allows to assess inhibitory processing, vital to the allocation of attention.},
      doi       = {10.1109/ner.2013.6696192},
    }
  • J. Ruckert, L. Haab, R. Hannemann, and D. J. Strauss, "Suppression of spontaneous activity in a computational tinnitus DCN model depends on notched-stimulation bandwidth," in 2013 6th International IEEE/EMBS Conference on Neural Engineering (NER), 2013, pp. 1406-1409. doi:10.1109/ner.2013.6696206
    [BibTeX] [Abstract]
    Early tinnitus onset is most likely attributed to an increased spontaneous activity caused by homeo-static plasticity effects in the peripheral auditory system. In a recent modeling study we demonstrated the effects of lateral inhibition on firing regularity related to an increased spontaneous activity. We found that increased activity causes the interconnected neurons to fire more regularly and synchronized. We hypothesized that a suppression of this orchestrated neural activity could be the physiological background of the tailor-made notched acoustic stimulation treatment as proposed by Okamoto and Pantev. In this article we want to highlight this neural activity alignment in the early stages of acoustic processing and examine the effects of different bandwiths of hearing loss and notched stimulation on the increased firing rate. We utilized a computation model of the dorsal cochlear nucleus by Zheng and Voigt with a modified input representing a hearing deficit and tinnitus as well as a notched acoustic stimulation. In-silico results show that the suppression of firing regularity in the frequency-range of the simulated tinnitus strongly depends on the relationship of the two bandwidths of the hearing deficit and the notched acoustic stimulation. The modulation of neural firing behaviour is thus strongly affected by edge effects, such as lateral inhibition bandwith or the slope of diminished neural excitation due to hearing deficit or stimulus notching.
    @InProceedings{ruckea2013,
      author    = {Ruckert, J. and Haab, L. and Hannemann, R. and Strauss, D. J.},
      booktitle = {2013 6th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Suppression of spontaneous activity in a computational tinnitus {DCN} model depends on notched-stimulation bandwidth},
      year      = {2013},
      month     = {nov},
      pages     = {1406-1409},
      publisher = {{IEEE}},
      abstract  = {Early tinnitus onset is most likely attributed to an increased spontaneous activity caused by homeo-static plasticity effects in the peripheral auditory system. In a recent modeling study we demonstrated the effects of lateral inhibition on firing regularity related to an increased spontaneous activity. We found that increased activity causes the interconnected neurons to fire more regularly and synchronized. We hypothesized that a suppression of this orchestrated neural activity could be the physiological background of the tailor-made notched acoustic stimulation treatment as proposed by Okamoto and Pantev. In this article we want to highlight this neural activity alignment in the early stages of acoustic processing and examine the effects of different bandwiths of hearing loss and notched stimulation on the increased firing rate. We utilized a computation model of the dorsal cochlear nucleus by Zheng and Voigt with a modified input representing a hearing deficit and tinnitus as well as a notched acoustic stimulation. In-silico results show that the suppression of firing regularity in the frequency-range of the simulated tinnitus strongly depends on the relationship of the two bandwidths of the hearing deficit and the notched acoustic stimulation. The modulation of neural firing behaviour is thus strongly affected by edge effects, such as lateral inhibition bandwith or the slope of diminished neural excitation due to hearing deficit or stimulus notching.},
      doi       = {10.1109/ner.2013.6696206},
    }
  • J. K. Schubert, E. González-Trejo, W. Retz, M. Rösler, T. Teuber, G. Steidl, D. J. Strauss, and F. I. Corona-Strauss, "Extracting cortical inhibition correlates in ERP-images within adult ADHD," in 2013 6th International IEEE/EMBS Conference on Neural Engineering (NER), 2013, pp. 513-516. doi:10.1109/ner.2013.6695984
    [BibTeX] [Abstract]
    ADHD presents a considerable social burden in adult life, and until recently was thought to be exclusive of children and adolescents. Techniques for an optimized diagnosis (based on electrophysiology) have been proven useful. In this paper, we present a new method for processing chirp-evoked, paired auditory late responses within the original time-domain, through two-dimensional image processing, using the non-local means approach. Results show effective denoising of cortical inhibition correlates in single sequences, which leads to an enhanced recognition of physiological features with fewer trials, as compared to averaging methods, reducing data loss and acquisition time. These results allow to optimize diagnosis by providing useful pointers regarding cortical inhibition within adult ADHD.
    @InProceedings{schuea2013,
      author    = {Schubert, J. K. and Gonz\'{a}lez-Trejo, E. and Retz, W. and R\"{o}sler, M. and Teuber, T. and Steidl, G. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {2013 6th International {IEEE}/{EMBS} Conference on Neural Engineering ({NER})},
      title     = {Extracting cortical inhibition correlates in {ERP}-images within adult {ADHD}},
      year      = {2013},
      month     = {nov},
      pages     = {513-516},
      publisher = {{IEEE}},
      abstract  = {ADHD presents a considerable social burden in adult life, and until recently was thought to be exclusive of children and adolescents. Techniques for an optimized diagnosis (based on electrophysiology) have been proven useful. In this paper, we present a new method for processing chirp-evoked, paired auditory late responses within the original time-domain, through two-dimensional image processing, using the non-local means approach. Results show effective denoising of cortical inhibition correlates in single sequences, which leads to an enhanced recognition of physiological features with fewer trials, as compared to averaging methods, reducing data loss and acquisition time. These results allow to optimize diagnosis by providing useful pointers regarding cortical inhibition within adult ADHD.},
      doi       = {10.1109/ner.2013.6695984},
    }

2012

  • F. I. Corona-Strauss, D. W., B. Schick, and D. J. Strauss, "Notched-Noise Embedded Frequency Specific Chirps for Objective Audiometry Using Auditory Brainstem Responses," Audiology Research, vol. 2e7, iss. 1, pp. 30-38, 2012. doi:10.4081/audiores.2012.e7
    [BibTeX] [Abstract]
    It has been shown recently that chirp-evoked auditory brainstem responses (ABRs) show better performance than click stimulations, especially at low intensity levels. In this paper we present the development, test, and evaluation of a series of notched-noise embedded frequency specific chirps. ABRs were collected in healthy young control subjects using the developed stimuli. Results of the analysis of the corresponding ABRs using a time-scale phase synchronization stability (PSS) measure are also reported. The resultant wave V amplitude and latency measures showed a similar behavior as for values reported in literature. The PSS of frequency specific chirp-evoked ABRs reflected the presence of the wave V for all stimulation intensities. The scales that resulted in higher PSS are in line with previous findings, where ABRs evoked by broadband chirps were analyzed, and which stated that low frequency channels are better for the recognition and analysis of chirp-evoked ABRs. We conclude that the development and test of the series of notched-noise embedded frequency specific chirps allowed the assessment of frequency specific ABRs, showing an identifiable wave V for different intensity levels. Future work may include the development of a faster automatic recognition scheme for these frequency specific ABRs.
    @Article{coroea2012,
      author    = {Corona-Strauss, F. I. and Delb W. and Schick, B. and Strauss, D. J.},
      journal   = {Audiology Research},
      title     = {Notched-Noise Embedded Frequency Specific Chirps for Objective Audiometry Using Auditory Brainstem Responses},
      year      = {2012},
      month     = {feb},
      number    = {1},
      pages     = {30-38},
      volume    = {2e7},
      abstract  = {It has been shown recently that chirp-evoked auditory brainstem responses (ABRs) show better performance than click stimulations, especially at low intensity levels. In this paper we present the development, test, and evaluation of a series of notched-noise embedded frequency specific chirps. ABRs were collected in healthy young control subjects using the developed stimuli. Results of the analysis of the corresponding ABRs using a time-scale phase synchronization stability (PSS) measure are also reported. The resultant wave V amplitude and latency measures showed a similar behavior as for values reported in literature. The PSS of frequency specific chirp-evoked ABRs reflected the presence of the wave V for all stimulation intensities. The scales that resulted in higher PSS are in line with previous findings, where ABRs evoked by broadband chirps were analyzed, and which stated that low frequency channels are better for the recognition and analysis of chirp-evoked ABRs. We conclude that the development and test of the series of notched-noise embedded frequency specific chirps allowed the assessment of frequency specific ABRs, showing an identifiable wave V for different intensity levels. Future work may include the development of a faster automatic recognition scheme for these frequency specific ABRs.},
      doi       = {10.4081/audiores.2012.e7},
      publisher = {{MDPI} {AG}},
    }
  • M. Mariam, W. Delb, B. Schick, and D. J. Strauss, "Objective Loudness Scaling by Late Auditory Evoked Potentials : Kernel Based Novelty Detection Approach," Artificial Intelligence in Medicine, vol. 55, pp. 185-195, 2012.
    [BibTeX]
    @Article{mariea2012,
      author  = {Mariam, M. and Delb, W. and Schick, B. and Strauss, D. J.},
      journal = {Artificial Intelligence in Medicine},
      title   = {Objective Loudness Scaling by Late Auditory Evoked Potentials : Kernel Based Novelty Detection Approach},
      year    = {2012},
      pages   = {185-195},
      volume  = {55},
    }
  • W. Retz, E. González-Trejo, F. Philipp-Wiegmann, K. D. Römer, P. Reinert, Y. F. Low, S. Boureghda, M. Rösler, and D. J. Strauss, "Assessment of Postexcitatory Long-Interval Cortical Inhibition in Adult Attention-Deficit/Hyperactivity Disorder," European Archives of Psychiatry and Clinical Neuroscience, vol. 262, pp. 507-517, 2012. doi:10.1007/s00406-012-0299-6
    [BibTeX] [Abstract]
    In order to further examine cortical impairment in adult ADHD patients and to test the hypothesis of a disturbed neuronal inhibition in adults with ADHD, late auditory evoked potentials were measured. By using paired-chirp auditory late responses, we compared 15 adults with ADHD with 15 control subjects, focusing on the inhibition elicited by the stimuli. Besides amplitude measurements, a time-frequency phase coherence study using the wavelet phase synchronization stability (WPSS) was performed. ADHD was diagnosed according to DSMIV criteria. All ADHD subjects were without medication and did not suffer from any further axis I disorder. WPSS analysis revealed impaired auditory inhibition for ADHD patients for interstimulus intervals (ISI) between 500 and 1,100 ms as compared with healthy controls. By analyzing the WPSS in the interval from 80 ms to 220 ms, mean inhibition of the test chirp was found to be 6% in the ADHD group and 38.5% in the control subjects (p = 0.01). Moreover, overall smaller amplitudes in the N100 and P200 waves at all ISI were found (p = 0.04 and p = 0.02). However, reproducibility indices in the amplitude measurements were low, thus supporting the use of the instantaneous phase-based analysis method. The results support the hypothesis of reduced intracortical inhibition as a correlate of disturbed brain function in adults with ADHD.
    @Article{retzea2012,
      author   = {Retz, W. and Gonz\'{a}lez-Trejo, E. and Philipp-Wiegmann, F. and R\"{o}mer, K. D. and Reinert, P. and Low, Y. F. and Boureghda, S. and R\"{o}sler, M. and Strauss, D. J.},
      journal  = {European Archives of Psychiatry and Clinical Neuroscience},
      title    = {Assessment of Postexcitatory Long-Interval Cortical Inhibition in Adult Attention-Deficit/Hyperactivity Disorder},
      year     = {2012},
      pages    = {507-517},
      volume   = {262},
      abstract = {In order to further examine cortical impairment in adult ADHD patients and to test the hypothesis of a disturbed neuronal inhibition in adults with ADHD, late auditory evoked potentials were measured. By using paired-chirp auditory late responses, we compared 15 adults with ADHD with 15 control subjects, focusing on the inhibition elicited by the stimuli. Besides amplitude measurements, a time-frequency phase coherence study using the wavelet phase synchronization stability (WPSS) was performed. ADHD was diagnosed according to DSMIV criteria. All ADHD subjects were without medication and did not suffer from any further axis I disorder. WPSS analysis revealed impaired auditory inhibition for ADHD patients for interstimulus intervals (ISI) between 500 and 1,100 ms as compared with healthy controls. By analyzing the WPSS in the interval from 80 ms to 220 ms, mean inhibition of the test chirp was found to be 6% in the ADHD group and 38.5% in the control subjects (p = 0.01). Moreover, overall smaller amplitudes in the N100 and P200 waves at all ISI were found (p = 0.04 and p = 0.02). However, reproducibility indices in the amplitude measurements were low, thus supporting the use of the instantaneous phase-based analysis method. The results support the hypothesis of reduced intracortical inhibition as a correlate of disturbed brain function in adults with ADHD.},
      doi      = {10.1007/s00406-012-0299-6},
      keywords = {Adult ADHD,ERP,Inhibition,Neurophysiology,Wavelet phase synchronization stability},
    }
  • C. Bernarding, D. J. Strauss, R. Hannemann, and F. I. Corona-Strauss, "Quantification of Listening Effort Correlates in the Oscillatory EEG Activity: A Feasibility Study," in Conf Proc IEEE Eng Med Biol Soc, 2012, pp. 4615-4618. doi:10.1109/embc.2012.6346995
    [BibTeX] [Abstract]
    So far, a generally accepted objective measure for the listening effort estimation in clinical settings is not existent. Such a measure could support the hearing aid fitting in order to reduce the listening effort in hearing impaired patients by an adequate adaption of their personal hearing aids.
    @InProceedings{bernea2012,
      author    = {Bernarding, C. and Strauss, D. J. and Hannemann, R. and Corona-Strauss, F. I.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Quantification of Listening Effort Correlates in the Oscillatory EEG Activity: A Feasibility Study},
      year      = {2012},
      pages     = {4615-4618},
      volume    = {2012:1},
      abstract  = {So far, a generally accepted objective measure for the listening effort estimation in clinical settings is not existent. Such a measure could support the hearing aid fitting in order to reduce the listening effort in hearing impaired patients by an adequate adaption of their personal hearing aids.},
      doi       = {10.1109/embc.2012.6346995},
    }
  • M. Busse, A. Kregeloh, E. Arzt, and D. J. Strauss, "Modeling the Influences of Nanoparticles on Neural Field Oscillations in Thalamocortical Networks," in Conf Proc IEEE Eng Med Biol Soc, 2012, pp. 1230-1233. doi:10.1109/embc.2012.6346159
    [BibTeX] [Abstract]
    The purpose of this study is twofold. First, we present a simplified multiscale modeling approach integrating activity on the scale of ionic channels into the spatiotemporal scale of neural field potentials: Resting upon a Hodgkin-Huxley based single cell model we introduced a neuronal feedback circuit based on the Llinás-model of thalamocortical activity and binding, where all cell specific intrinsic properties were adopted from patch-clamp measurements. In this paper, we expand this existing model by integrating the output to the spatiotemporal scale of field potentials. Those are supposed to originate from the parallel activity of a variety of synchronized thalamocortical columns at the quasi-microscopic level, where the involved neurons are gathered together in units. Second and more important, we study the possible effects of nanoparticles (NPs) that are supposed to interact with thalamic cells of our network model. In two preliminary studies we demonstrated in vitro and in vivo effects of NPs on the ionic channels of single neurons and thereafter on neuronal feedback circuits. By means of our new model we assumed now NPs induced changes on the ionic currents of the involved thalamic neurons. Here we found extensive diversified pattern formations of neural field potentials when comparing to the modeled activity without neuromodulating NPs addition. This model provides predictions about the influences of NPs on spatiotemporal neural field oscillations in thalamocortical networks. These predictions can be validated by high spatiotemporal resolution electrophysiological measurements like voltage sensitive dyes and multiarray recordings.
    @InProceedings{bussea2012,
      author    = {Busse, M. and Kregeloh, A. and Arzt, E. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Modeling the Influences of Nanoparticles on Neural Field Oscillations in Thalamocortical Networks},
      year      = {2012},
      pages     = {1230-1233},
      volume    = {2012:1},
      abstract  = {The purpose of this study is twofold. First, we present a simplified multiscale modeling approach integrating activity on the scale of ionic channels into the spatiotemporal scale of neural field potentials: Resting upon a Hodgkin-Huxley based single cell model we introduced a neuronal feedback circuit based on the Llin{\'{a}}s-model of thalamocortical activity and binding, where all cell specific intrinsic properties were adopted from patch-clamp measurements. In this paper, we expand this existing model by integrating the output to the spatiotemporal scale of field potentials. Those are supposed to originate from the parallel activity of a variety of synchronized thalamocortical columns at the quasi-microscopic level, where the involved neurons are gathered together in units. Second and more important, we study the possible effects of nanoparticles (NPs) that are supposed to interact with thalamic cells of our network model. In two preliminary studies we demonstrated in vitro and in vivo effects of NPs on the ionic channels of single neurons and thereafter on neuronal feedback circuits. By means of our new model we assumed now NPs induced changes on the ionic currents of the involved thalamic neurons. Here we found extensive diversified pattern formations of neural field potentials when comparing to the modeled activity without neuromodulating NPs addition. This model provides predictions about the influences of NPs on spatiotemporal neural field oscillations in thalamocortical networks. These predictions can be validated by high spatiotemporal resolution electrophysiological measurements like voltage sensitive dyes and multiarray recordings.},
      doi       = {10.1109/embc.2012.6346159},
    }
  • L. Haab, M. Scheerer, J. Ruckert, R. Hannemann, and D. J. Strauss, "Support of a patient-specific therapeutical acoustic stimulation in tinnitus by numerical modeling," in Conf Proc IEEE Eng Med Biol Soc, 2012, pp. 5578-5581. doi:10.1109/embc.2012.6347258
    [BibTeX] [Abstract]
    The pathogenesis of tinnitus involves multiple hierarchical levels of auditory processing and appraisal of sensory saliency. Early tinnitus onset is most likely attributed to homeostatic plasticity in the periphery, while the chronification and decompensation are tightly linked to brain areas for the allocation of attentional resources, such as e.g., the thalamocortical feedback loops and the limbic system. Increased spontaneous firing after sensory deafferentation might be sufficient to generate a phantom perception, yet the question why not every peripheral hearing loss automatically elicits a tinnitus sensation is still to be addressed. Utilizing quantitative modeling of multiple hierarchical levels in the auditory pathway, we demonstrate the effects of lateral inhibition on increased spontaneous firing and the resulting elevation of firing regularity and synchronization of neural activity. The presented therapeutical approach is based on the idea of disrupting the heightened regularity of the neural population response in the tinnitus frequency range. This neural activity regularity depends on lateral dispersion of common noise and thus is susceptible for edge effects and might be influenced by a change in neural activity in bordering frequency ranges by fitted acoustical stimulation. We propose the use of patient specifically adapted tailor-made notched acoustic stimulation, utilizing modeling results for the optimal adjustment of the stimulation frequencies to archive a therapeutical edge-effect.
    @InProceedings{haabea2012,
      author    = {Haab, L. and Scheerer, M. and Ruckert, J. and Hannemann, R. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Support of a patient-specific therapeutical acoustic stimulation in tinnitus by numerical modeling},
      year      = {2012},
      pages     = {5578-5581},
      volume    = {2012:1},
      abstract  = {The pathogenesis of tinnitus involves multiple hierarchical levels of auditory processing and appraisal of sensory saliency. Early tinnitus onset is most likely attributed to homeostatic plasticity in the periphery, while the chronification and decompensation are tightly linked to brain areas for the allocation of attentional resources, such as e.g., the thalamocortical feedback loops and the limbic system. Increased spontaneous firing after sensory deafferentation might be sufficient to generate a phantom perception, yet the question why not every peripheral hearing loss automatically elicits a tinnitus sensation is still to be addressed. Utilizing quantitative modeling of multiple hierarchical levels in the auditory pathway, we demonstrate the effects of lateral inhibition on increased spontaneous firing and the resulting elevation of firing regularity and synchronization of neural activity. The presented therapeutical approach is based on the idea of disrupting the heightened regularity of the neural population response in the tinnitus frequency range. This neural activity regularity depends on lateral dispersion of common noise and thus is susceptible for edge effects and might be influenced by a change in neural activity in bordering frequency ranges by fitted acoustical stimulation. We propose the use of patient specifically adapted tailor-made notched acoustic stimulation, utilizing modeling results for the optimal adjustment of the stimulation frequencies to archive a therapeutical edge-effect.},
      doi       = {10.1109/embc.2012.6347258},
    }
  • J. K. Schubert, T. Teuber, G. Steidl, D. J. Strauss, and F. I. Corona-Strauss, "Nonlocal two dimensional denoising of frequency specific chirp evoked ABR single trials," in Conf Proc IEEE Eng Med Biol Soc, 2012, pp. 2527-2530. doi:10.1109/embc.2012.6346478
    [BibTeX] [Abstract]
    Recently, we have shown that denoising evoked potential (EP) images is possible using two dimensional diffusion filtering methods. This restoration allows for an integration of regularities over multiple stimulations into the denoising process. In the present work we propose the nonlocal means (NLM) method for EP image denoising. The EP images were constructed using auditory brainstem responses (ABR) collected in young healthy subjects using frequency specific and broadband chirp stimulations. It is concluded that the NLM method is more efficient than conventional approaches in EP imaging denoising, specially in the case of ABRs, where the relevant information can be easily masked by the ongoing EEG activity, i.e., signals suffer from rather low signal-to-noise ratio SNR. The proposed approach is for the a posteriori denoising of single trials after the experiment and not for real time applications.
    @InProceedings{schuea2012,
      author    = {Schubert, J. K. and Teuber, T. and Steidl, G. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Nonlocal two dimensional denoising of frequency specific chirp evoked ABR single trials},
      year      = {2012},
      pages     = {2527-2530},
      volume    = {2012:1},
      abstract  = {Recently, we have shown that denoising evoked potential (EP) images is possible using two dimensional diffusion filtering methods. This restoration allows for an integration of regularities over multiple stimulations into the denoising process. In the present work we propose the nonlocal means (NLM) method for EP image denoising. The EP images were constructed using auditory brainstem responses (ABR) collected in young healthy subjects using frequency specific and broadband chirp stimulations. It is concluded that the NLM method is more efficient than conventional approaches in EP imaging denoising, specially in the case of ABRs, where the relevant information can be easily masked by the ongoing EEG activity, i.e., signals suffer from rather low signal-to-noise ratio SNR. The proposed approach is for the a posteriori denoising of single trials after the experiment and not for real time applications.},
      doi       = {10.1109/embc.2012.6346478},
    }

2011

  • A. Harris, K. Schwerdtfeger, and D. J. Strauss, "Adapted Filter Banks for Feature Extraction in Transcranial Magnetic Stimulation Evoked Responses," Medical and Biological Engineering and Computing, vol. 49, pp. 221-231, 2011. doi:10.1007/s11517-010-0726-7
    [BibTeX] [Abstract]
    A novel adaptive and approximate shift-invariant wavelet packet feature extraction scheme for event-related potentials (ERPs) in the electroencephalogram (EEG) is introduced in this paper. In this algorithm, the shift-invariant wavelet packed decomposition is done by integrating a cost function for decimation decision in each sub-band expansion. Additionally, a shape adaptation of the wavelet is implemented to find the best adapted wavelet shape for a given class of ERPs. This scheme is used to analyze the time course of the impact of single-pulse transcranial magnetic stimulation (TMS) to the auditory ERPs. We show that the proposed scheme is able to extract even slightest impacts of TMS, making it a promising tool for the extraction of weak ERPs components, particularly in hybrid TMS-EEG/ERP setups.
    @Article{harrea2011,
      author   = {Harris, A. and Schwerdtfeger, K. and Strauss, D. J.},
      journal  = {Medical and Biological Engineering and Computing},
      title    = {Adapted Filter Banks for Feature Extraction in Transcranial Magnetic Stimulation Evoked Responses},
      year     = {2011},
      pages    = {221-231},
      volume   = {49},
      abstract = {A novel adaptive and approximate shift-invariant wavelet packet feature extraction scheme for event-related potentials (ERPs) in the electroencephalogram (EEG) is introduced in this paper. In this algorithm, the shift-invariant wavelet packed decomposition is done by integrating a cost function for decimation decision in each sub-band expansion. Additionally, a shape adaptation of the wavelet is implemented to find the best adapted wavelet shape for a given class of ERPs. This scheme is used to analyze the time course of the impact of single-pulse transcranial magnetic stimulation (TMS) to the auditory ERPs. We show that the proposed scheme is able to extract even slightest impacts of TMS, making it a promising tool for the extraction of weak ERPs components, particularly in hybrid TMS-EEG/ERP setups.},
      doi      = {10.1007/s11517-010-0726-7},
      keywords = {EEG,Feature extraction,Filter banks,Shift-invariant,Transcranial magnetic stimulation},
    }
  • L. Haab, C. Trenado, M. Mariam, and D. J. Strauss, "Neurofunctional Model of Large-Scale Correlates of Selective Attention Governed by Stimulus-Novelty," Cognitive Neurodynamics, vol. 5, iss. 1, pp. 103-111, 2011. doi:10.1007/s11571-010-9150-9
    [BibTeX] [Abstract]
    Multiple studies demonstrate the influence of the limbic system on the processing of sensory events and attentional guidance. But the mechanisms involved therein are yet not entirely clear. The close connection of handling incoming sensory information and memory retrieval, like in the case of habituation towards insignificant stimuli, suggests a crucial impact of the hippocampus on the direction of attention. In this paper we thus present a neurofunctional forward model of a hippocampal comparator function based on the theory of theta-regulated attention. Subsequently we integrated this comparator model into a multiscale framework for the simulation of evoked responses. The results of our simulations were compared to experimental data on electroencephalographic (EEG) correlates of habituation towards familiar stimuli using time-scale analysis. In consequence we are able to present additional evidence for limbic influences on the direction of attention driven by stimulus novelty and a systems neuroscience framework for the statements given in the theta-regulated attention hypothesis.
    @Article{haabea2011,
      author    = {Haab, L. and Trenado, C. and Mariam, M. and Strauss, D. J.},
      journal   = {Cognitive Neurodynamics},
      title     = {Neurofunctional Model of Large-Scale Correlates of Selective Attention Governed by Stimulus-Novelty},
      year      = {2011},
      month     = {jan},
      number    = {1},
      pages     = {103-111},
      volume    = {5},
      abstract  = {Multiple studies demonstrate the influence of the limbic system on the processing of sensory events and attentional guidance. But the mechanisms involved therein are yet not entirely clear. The close connection of handling incoming sensory information and memory retrieval, like in the case of habituation towards insignificant stimuli, suggests a crucial impact of the hippocampus on the direction of attention. In this paper we thus present a neurofunctional forward model of a hippocampal comparator function based on the theory of theta-regulated attention. Subsequently we integrated this comparator model into a multiscale framework for the simulation of evoked responses. The results of our simulations were compared to experimental data on electroencephalographic (EEG) correlates of habituation towards familiar stimuli using time-scale analysis. In consequence we are able to present additional evidence for limbic influences on the direction of attention driven by stimulus novelty and a systems neuroscience framework for the statements given in the theta-regulated attention hypothesis.},
      doi       = {10.1007/s11571-010-9150-9},
      keywords  = {Attention,Comparator,EEG,Evoked responses,Hippocampus,Oscillatory model,Stimulus novelty,Synchronization},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • Y. F. Low and D. J. Strauss, "A Performance Study of the Wavelet-Phase Stability Measure in Auditory Selective Attention," Brain Research Bulletin, vol. 86, pp. 110-117, 2011. doi:10.1016/j.brainresbull.2011.06.012
    [BibTeX] [Abstract]
    Large-scale neural correlates of auditory selective attention reflected in the electroencephalogram (EEG) have been identified by using the complex wavelet-phase stability measure (WPS). In this paper, we study the feasibility of using this amplitude independent measure, the WPS in extracting the correlates of attention by comparing its performance to the widely used linear interdependency measures, i.e., the wavelet coherence and the correlation coefficient. The outcome reveals that the WPS outperforms the other two measures in discriminating both the attended and unattended single sweep auditory late responses (ALRs). It is concluded that the proposed WPS provides a faster (in terms of less sweeps which are required) and robust objective quantification of selective attention.
    @Article{lowea2011,
      author   = {Low, Y. F. and Strauss, D. J.},
      journal  = {Brain Research Bulletin},
      title    = {A Performance Study of the Wavelet-Phase Stability Measure in Auditory Selective Attention},
      year     = {2011},
      pages    = {110-117},
      volume   = {86},
      abstract = {Large-scale neural correlates of auditory selective attention reflected in the electroencephalogram (EEG) have been identified by using the complex wavelet-phase stability measure (WPS). In this paper, we study the feasibility of using this amplitude independent measure, the WPS in extracting the correlates of attention by comparing its performance to the widely used linear interdependency measures, i.e., the wavelet coherence and the correlation coefficient. The outcome reveals that the WPS outperforms the other two measures in discriminating both the attended and unattended single sweep auditory late responses (ALRs). It is concluded that the proposed WPS provides a faster (in terms of less sweeps which are required) and robust objective quantification of selective attention.},
      doi      = {10.1016/j.brainresbull.2011.06.012},
      keywords = {Auditory selective attention,Correlation coefficient,Wavelet coherence,Wavelet phase-stability},
    }
  • C. Trenado, M. Wittmar, M. Veith, N. C. Rosero-Navarro, M. Aparicio, A. Duran, Y. Castro, and D. J. Strauss, "Multiscale numerical modeling of Ce3+-inhibitor release from novel corrosion protection coatings," Modelling and Simulation in Materials Science and Engineering, vol. 19, iss. 2, pp. 110-119, 2011. doi:10.1088/0965-0393/19/2/025009
    [BibTeX] [Abstract]
    A novel hybrid sol-gel coating has recently been introduced as an alternative to high toxic chromate-based corrosion protection systems. In this paper, we propose a multiscale computational model to estimate the amount and time scale of inhibitor release of the active corrosion protection coating. Moreover, we study the release rate under the influence of parameters such as porosity and viscosity, which have recently been implicated in the stability of the coating. Numerical simulations obtained with the model predicted experimental release tests and recent findings on the compromise between inhibitor concentration and the stability of the coating.
    @Article{trenea2011,
      author    = {Trenado, C. and Wittmar, M. and Veith, M. and Rosero-Navarro, N. C. and Aparicio, M. and Duran, A. and Castro, Y. and Strauss, D. J.},
      journal   = {Modelling and Simulation in Materials Science and Engineering},
      title     = {Multiscale numerical modeling of Ce3+-inhibitor release from novel corrosion protection coatings},
      year      = {2011},
      month     = {feb},
      number    = {2},
      pages     = {110-119},
      volume    = {19},
      abstract  = {A novel hybrid sol-gel coating has recently been introduced as an alternative to high toxic chromate-based corrosion protection systems. In this paper, we propose a multiscale computational model to estimate the amount and time scale of inhibitor release of the active corrosion protection coating. Moreover, we study the release rate under the influence of parameters such as porosity and viscosity, which have recently been implicated in the stability of the coating. Numerical simulations obtained with the model predicted experimental release tests and recent findings on the compromise between inhibitor concentration and the stability of the coating.},
      doi       = {10.1088/0965-0393/19/2/025009},
      publisher = {{IOP} Publishing},
    }
  • C. Bernarding, M. Latzel, D. J. Strauss, and F. I. Corona-Strauss, "On the objective electrophysiological estimation of listening effort in different age groups," in Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on, 2011, pp. 671-674. doi:10.1109/ner.2011.5910637
    [BibTeX] [Abstract]
    The basic approaches to fit hearing aids were commonly based on findings of how young persons hear sounds in ideal conditions. In order to improve hearing aid fitting methods, the focus of the new approaches should be based on auditory processing and cognition information of older adults. In previous studies with young subjects, employing tonebursts and in noise embedded syllabic paradigms, we have shown that the Wavelet Phase Synchronization Stability (WPSS) of Auditory Late Responses (ALRs) can serve as an objective indicator of listening effort. The purpose of this preliminary work, which precedes a study with hearing impaired persons, is to examine possible age-related differences in the WPSS and ALRs by testing syllabic paradigms in two different age groups and using two different levels of task complexity. The WPSS discriminated between difficult and easy test conditions, which is in line with our previous findings. The latest was consistent in both age groups. Age-related differences regarding the WPSS could not be observed.
    @InProceedings{bernea2011,
      author    = {Bernarding, C. and Latzel, M. and Strauss, D. J. and Corona-Strauss, F. I.},
      booktitle = {Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on},
      title     = {On the objective electrophysiological estimation of listening effort in different age groups},
      year      = {2011},
      month     = {apr},
      pages     = {671-674},
      publisher = {{IEEE}},
      volume    = {NER2011},
      abstract  = {The basic approaches to fit hearing aids were commonly based on findings of how young persons hear sounds in ideal conditions. In order to improve hearing aid fitting methods, the focus of the new approaches should be based on auditory processing and cognition information of older adults. In previous studies with young subjects, employing tonebursts and in noise embedded syllabic paradigms, we have shown that the Wavelet Phase Synchronization Stability (WPSS) of Auditory Late Responses (ALRs) can serve as an objective indicator of listening effort. The purpose of this preliminary work, which precedes a study with hearing impaired persons, is to examine possible age-related differences in the WPSS and ALRs by testing syllabic paradigms in two different age groups and using two different levels of task complexity. The WPSS discriminated between difficult and easy test conditions, which is in line with our previous findings. The latest was consistent in both age groups. Age-related differences regarding the WPSS could not be observed.},
      doi       = {10.1109/ner.2011.5910637},
    }
  • C. Bernarding, D. J. Strauss, M. Latzel, R. Hannemann, J. Chalupper, and F. I. Corona-Strauss, "Simulations of hearing loss and hearing aid: Effects on electrophysiological correlates of listening effort," in Conf Proc IEEE Eng Med Biol Soc, 2011, pp. 2319-2322. doi:10.1109/iembs.2011.6090649
    [BibTeX] [Abstract]
    In the last decades, many investigations were done to examine the effects of sensorineural hearing loss on the speech perception ability. Besides testing hearing impaired persons, there is also the possibility to simulate the hearing loss. Therefore, some electrophysiological as well as speech recognition studies were performed in normal hearing subjects using techniques to model the sensorineural hearing loss. Thus, the effects of peripheral hearing loss without central auditory pathologies can be examined. In previous studies, we have shown, that the wavelet phase synchronization stability (WPSS) of auditory late responses could serve as a possible indicator of listening effort. Now, the aims of this present study were to explore the effects on the WPSS by using two different simulations of hearing loss and a simulated hearing aid. The preliminary results showed, that in case of a simultaneous simulation of hearing loss by noise masking and a hearing aid, an objective discrimination between an easy and a difficult listening situation can be achieved. Furthermore, the WPSS reflected also a good discrimination by using the filtered and attenuated paradigms.
    @InProceedings{bernea2011b,
      author    = {Bernarding, C. and Strauss, D. J. and Latzel, M. and Hannemann, R. and Chalupper, J. and Corona-Strauss, F. I.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Simulations of hearing loss and hearing aid: Effects on electrophysiological correlates of listening effort},
      year      = {2011},
      month     = {aug},
      pages     = {2319-2322},
      publisher = {{IEEE}},
      volume    = {2011:1},
      abstract  = {In the last decades, many investigations were done to examine the effects of sensorineural hearing loss on the speech perception ability. Besides testing hearing impaired persons, there is also the possibility to simulate the hearing loss. Therefore, some electrophysiological as well as speech recognition studies were performed in normal hearing subjects using techniques to model the sensorineural hearing loss. Thus, the effects of peripheral hearing loss without central auditory pathologies can be examined. In previous studies, we have shown, that the wavelet phase synchronization stability (WPSS) of auditory late responses could serve as a possible indicator of listening effort. Now, the aims of this present study were to explore the effects on the WPSS by using two different simulations of hearing loss and a simulated hearing aid. The preliminary results showed, that in case of a simultaneous simulation of hearing loss by noise masking and a hearing aid, an objective discrimination between an easy and a difficult listening situation can be achieved. Furthermore, the WPSS reflected also a good discrimination by using the filtered and attenuated paradigms.},
      doi       = {10.1109/iembs.2011.6090649},
    }
  • F. I. Corona-Strauss, C. Bernarding, M. Latzel, and D. J. Strauss, "Syllable evoked auditory late responses: Effects of noise onsets and noise types," in Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on, 2011, pp. 140-143. doi:10.1109/ner.2011.5910508
    [BibTeX] [Abstract]
    Listening in noisy situations demands cognitive effort. Recently, we have shown that the Wavelet Phase Synchronization Stability (WPSS) of Auditory Late Responses (ALRs) represents an objective method to estimate mental load in auditory environments. In literature only a limited number of publications can be found which focus on the effects of noise types and noise onset effects using syllable evoked ALRs. The objective of the present work was to analyze the influence of different parameters, like white and babble noise as well as different noise onset times 50, 300, 1000ms and continuous noise conditions, on syllable evoked ALRs. Also, the analysis of the WPSS, as used in previous work, has never been applied to see such effects on the ALRs. We found that noise onset times of 300ms or larger showed a good separation of the ALR components. Furthermore, the analysis of the WPSS for different scales showed a clear identification of the N1 components. However, the best type of noise, and noise onset configuration depends on the specific application. For investigations related to auditory processing of speech, ecological noises are preferred because they could be used to mimic everyday listening situations.
    @InProceedings{coroea2011,
      author    = {Corona-Strauss, F. I. and Bernarding, C. and Latzel, M. and Strauss, D. J.},
      booktitle = {Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on},
      title     = {Syllable evoked auditory late responses: Effects of noise onsets and noise types},
      year      = {2011},
      pages     = {140-143},
      abstract  = {Listening in noisy situations demands cognitive effort. Recently, we have shown that the Wavelet Phase Synchronization Stability (WPSS) of Auditory Late Responses (ALRs) represents an objective method to estimate mental load in auditory environments. In literature only a limited number of publications can be found which focus on the effects of noise types and noise onset effects using syllable evoked ALRs. The objective of the present work was to analyze the influence of different parameters, like white and babble noise as well as different noise onset times 50, 300, 1000ms and continuous noise conditions, on syllable evoked ALRs. Also, the analysis of the WPSS, as used in previous work, has never been applied to see such effects on the ALRs. We found that noise onset times of 300ms or larger showed a good separation of the ALR components. Furthermore, the analysis of the WPSS for different scales showed a clear identification of the N1 components. However, the best type of noise, and noise onset configuration depends on the specific application. For investigations related to auditory processing of speech, ecological noises are preferred because they could be used to mimic everyday listening situations.},
      doi       = {10.1109/ner.2011.5910508},
    }
  • E. González-Trejo, F. Philipp-Wiegmann, K. D. Römer, P. Reinert, Y. F. Low, S. Boureghda, W. Retz, M. Rösler, and D. J. Strauss, "Assessment of Cortical Inhibition in Adult Attention-Deficit/Hyperactivity Disorder by Paired-Chirp Auditory Evoked Potentials," in Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on, 2011. doi:10.1109/ner.2011.5910641
    [BibTeX] [Abstract]
    In order to further research cortical impairment in ADHD patients, late auditory evoked potentials were measured. By using paired-chirp auditory late responses, we compared the ADHD group against a control group, focusing on the inhibition elicited by the stimuli. The results show overall smaller amplitudes in the N100 and P200 waves, as well as a reduced inhibition in test chirp for ADHD patients. A frequency study using the wavelet phase synchronization stability transform was made in order to strengthen the results, as well as analysis of variance test for frequency and repro-ducibility index for amplitude. Both amplitude and frequency show there is an impaired auditory inhibition in ADHD patients, for interstimulus intervals of 500 and 700 ms, and reinforce the knowledge that impairments in this condition are present in multiple cortical areas.
    @InProceedings{gonzea2011,
      author    = {Gonz\'{a}lez-Trejo, E. and Philipp-Wiegmann, F. and R\"{o}mer, K.D. and Reinert, P. and Low, Y.F. and Boureghda, S. and Retz, W. and R\"{o}sler, M. and Strauss, D.J.},
      booktitle = {Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on},
      title     = {Assessment of Cortical Inhibition in Adult Attention-Deficit/Hyperactivity Disorder by Paired-Chirp Auditory Evoked Potentials},
      year      = {2011},
      abstract  = {In order to further research cortical impairment in ADHD patients, late auditory evoked potentials were measured. By using paired-chirp auditory late responses, we compared the ADHD group against a control group, focusing on the inhibition elicited by the stimuli. The results show overall smaller amplitudes in the N100 and P200 waves, as well as a reduced inhibition in test chirp for ADHD patients. A frequency study using the wavelet phase synchronization stability transform was made in order to strengthen the results, as well as analysis of variance test for frequency and repro-ducibility index for amplitude. Both amplitude and frequency show there is an impaired auditory inhibition in ADHD patients, for interstimulus intervals of 500 and 700 ms, and reinforce the knowledge that impairments in this condition are present in multiple cortical areas.},
      doi       = {10.1109/ner.2011.5910641},
    }
  • L. Haab, M. Busse, M. Mariam, T. Weis, and D. J. Strauss, "Detection of a novelty event in the identification of faces in a passive VEP task," in Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on, 2011, pp. 679-682. doi:10.1109/ner.2011.5910639
    [BibTeX] [Abstract]
    The degree of severity of several psychopathologies coming along with cognitive deficits often impedes the adequate execution of complex cognitive tasks, demanding for objective analysis of cognitive function in an easy-to-follow paradigm for uncooperative patients. The broad availability of electroencephalography (EEG) provides an auspicious base for the development of a fast and reliable tool for the objective diagnosis of pathological cognitive limitations. In the development of the paradigm and follow-up data analysis, we focussed on the objective assessment of the most common cognitive deficits in psychopathological disorders, i.e., limitations in working-memory span and the corresponding loss of attentional resources as well as deficits in facial recognition, contributing to severe social cuts. In a passive face recognition task, we monitored the N170 component of late visual evoked potentials (VEP) in healthy subjects for establishing a methodological base for the diagnostics of cognitive deficits in patients. In line with our preliminary work, we were able to demonstrate a loss of phasic coherence in the single-trial analysis of subsequent visual stimuli during the repetitive face presentation. The novelty event however involuntarily captures attentional resources, resulting in an afresh increase in intertrial phase coherence. These results provide a new viable methodology for accessing the novelty-effect in cognitive deficit patients using a passive visual ERP paradigm of involuntary attentional guidance and habituation.
    @InProceedings{haabea2011b,
      author    = {Haab, L. and Busse, M. and Mariam, M. and Weis, T. and Strauss, D. J.},
      booktitle = {Neural Engineering (NER), 2011 5th International IEEE/EMBS Conference on},
      title     = {Detection of a novelty event in the identification of faces in a passive VEP task},
      year      = {2011},
      pages     = {679-682},
      abstract  = {The degree of severity of several psychopathologies coming along with cognitive deficits often impedes the adequate execution of complex cognitive tasks, demanding for objective analysis of cognitive function in an easy-to-follow paradigm for uncooperative patients. The broad availability of electroencephalography (EEG) provides an auspicious base for the development of a fast and reliable tool for the objective diagnosis of pathological cognitive limitations. In the development of the paradigm and follow-up data analysis, we focussed on the objective assessment of the most common cognitive deficits in psychopathological disorders, i.e., limitations in working-memory span and the corresponding loss of attentional resources as well as deficits in facial recognition, contributing to severe social cuts. In a passive face recognition task, we monitored the N170 component of late visual evoked potentials (VEP) in healthy subjects for establishing a methodological base for the diagnostics of cognitive deficits in patients. In line with our preliminary work, we were able to demonstrate a loss of phasic coherence in the single-trial analysis of subsequent visual stimuli during the repetitive face presentation. The novelty event however involuntarily captures attentional resources, resulting in an afresh increase in intertrial phase coherence. These results provide a new viable methodology for accessing the novelty-effect in cognitive deficit patients using a passive visual ERP paradigm of involuntary attentional guidance and habituation.},
      doi       = {10.1109/ner.2011.5910639},
      keywords  = {EEG,N170,attention,cognitive deficit,face recognition,phasic coherence,single-trial analysis},
    }

2010

  • I. Mustaffa, C. Trenado, K. Schwerdtfeger, and D. J. Strauss, "Denoising of single-trial matrix representations using 2D nonlinear diffusion filtering," Journal of Neuroscience Methods, vol. 185, pp. 284-292, 2010. doi:10.1016/j.jneumeth.2009.09.017
    [BibTeX] [Abstract]
    In this paper we present a novel application of denoising by means of nonlinear diffusion filters (NDFs). NDFs have been successfully applied for image processing and computer vision areas, particularly in image denoising, smoothing, segmentation, and restoration. We apply two types of NDFs for the denoising of evoked responses in single-trials in a matrix form, the nonlinear isotropic and the anisotropic diffusion filters. We show that by means of NDFs we are able to denoise the evoked potentials resulting in a better extraction of physiologically relevant morphological features over the ongoing experiment. This technique offers the advantage of translation-invariance in comparison to other well-known methods, e.g., wavelet denoising based on maximally decimated filter banks, due to an adaptive diffusion feature. We compare the proposed technique with a wavelet denoising scheme that had been introduced before for evoked responses. It is concluded that NDFs represent a promising and useful approach in the denoising of event related potentials. Novel NDF applications of single-trials of auditory brain responses (ABRs) and the transcranial magnetic stimulation (TMS) evoked electroencephalographic responses denoising are presented in this paper.
    @Article{mustea2010,
      author   = {Mustaffa, I. and Trenado, C. and Schwerdtfeger, K. and Strauss, D. J.},
      journal  = {Journal of Neuroscience Methods},
      title    = {Denoising of single-trial matrix representations using 2D nonlinear diffusion filtering},
      year     = {2010},
      pages    = {284-292},
      volume   = {185},
      abstract = {In this paper we present a novel application of denoising by means of nonlinear diffusion filters (NDFs). NDFs have been successfully applied for image processing and computer vision areas, particularly in image denoising, smoothing, segmentation, and restoration. We apply two types of NDFs for the denoising of evoked responses in single-trials in a matrix form, the nonlinear isotropic and the anisotropic diffusion filters. We show that by means of NDFs we are able to denoise the evoked potentials resulting in a better extraction of physiologically relevant morphological features over the ongoing experiment. This technique offers the advantage of translation-invariance in comparison to other well-known methods, e.g., wavelet denoising based on maximally decimated filter banks, due to an adaptive diffusion feature. We compare the proposed technique with a wavelet denoising scheme that had been introduced before for evoked responses. It is concluded that NDFs represent a promising and useful approach in the denoising of event related potentials. Novel NDF applications of single-trials of auditory brain responses (ABRs) and the transcranial magnetic stimulation (TMS) evoked electroencephalographic responses denoising are presented in this paper.},
      doi      = {10.1016/j.jneumeth.2009.09.017},
      keywords = {Denoising,Evoked responses,Nonlinear diffusion filtering,Single-trials},
    }
  • D. J. Strauss, F. I. Corona-Strauss, C. Trenado, C. Bernarding, W. Reith, M. Latzel, and M. Froehlich, "Electrophysiological correlates of listening effort: neurodynamical modeling and measurement," Cognitive Neurodynamics, vol. 4, iss. 2, pp. 119-131, 2010. doi:10.1007/s11571-010-9111-3
    [BibTeX] [Abstract]
    An increased listing effort represents a major problem in humans with hearing impairment. Neurodiagnostic methods for an objective listening effort estimation might support hearing instrument fitting procedures. However the cognitive neurodynamics of listening effort is far from being understood and its neural correlates have not been identified yet. In this paper we analyze the cognitive neurodynamics of listening effort by using methods of forward neurophysical modeling and time-scale electroen-cephalographic neurodiagnostics. In particular, we present a forward neurophysical model for auditory late responses (ALRs) as large-scale listening effort correlates. Here endogenously driven top-down projections related to listening effort are mapped to corticothalamic feedback pathways which were analyzed for the selective attention neurodynamics before. We show that this model represents well the time-scale phase stability analysis of experimental electroencephalographic data from auditory discrimination paradigms. It is concluded that the proposed neurophysical and neuropsychological framework is appropriate for the analysis of listening effort and might help to develop objective electroencephalographic methods for its estimation in future.
    @Article{straea2010,
      author    = {Strauss, D. J. and Corona-Strauss, F. I. and Trenado, C. and Bernarding, C. and Reith, W. and Latzel, M. and Froehlich, M.},
      journal   = {Cognitive Neurodynamics},
      title     = {Electrophysiological correlates of listening effort: neurodynamical modeling and measurement},
      year      = {2010},
      month     = {apr},
      number    = {2},
      pages     = {119-131},
      volume    = {4},
      abstract  = {An increased listing effort represents a major problem in humans with hearing impairment. Neurodiagnostic methods for an objective listening effort estimation might support hearing instrument fitting procedures. However the cognitive neurodynamics of listening effort is far from being understood and its neural correlates have not been identified yet. In this paper we analyze the cognitive neurodynamics of listening effort by using methods of forward neurophysical modeling and time-scale electroen-cephalographic neurodiagnostics. In particular, we present a forward neurophysical model for auditory late responses (ALRs) as large-scale listening effort correlates. Here endogenously driven top-down projections related to listening effort are mapped to corticothalamic feedback pathways which were analyzed for the selective attention neurodynamics before. We show that this model represents well the time-scale phase stability analysis of experimental electroencephalographic data from auditory discrimination paradigms. It is concluded that the proposed neurophysical and neuropsychological framework is appropriate for the analysis of listening effort and might help to develop objective electroencephalographic methods for its estimation in future.},
      doi       = {10.1007/s11571-010-9111-3},
      keywords  = {Auditory evoked potentials,Gabor frames,Listening effort,Modeling,Phase synchronization,Single sweeps,Wavelets},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • C. Bernarding, F. I. Corona-Strauss, M. Latzel, and D. J. Strauss, "Auditory Streaming and Listening Effort: An Event-Related Potential Study," in Conf Proc IEEE Eng Med Biol Soc, 2010, pp. 6817-6820. doi:10.1109/iembs.2010.5625957
    [BibTeX] [Abstract]
    Until now, an objective method to estimate listening effort with a minimum level of cooperation of the patient in order to fit hearing aids is not existent. The benefit of such a method would be to reduce the listening effort in hearing impaired persons by an adequate adaption of the hearing aids. Recently, we have shown that the wavelet phase synchronization stability (WPSS) of auditory late responses could serve as a measure to estimate listening effort. In this paper, we extend our previous studies by using for the first time syllable stimulation paradigms with two levels of difficulty due to the combination of the syllables. Furthermore, by taking the model of auditory stream selection into account, the complexity of the paradigms was enhanced by the generation of a second competing auditory stream beside the syllable stream. This stream consisted of multitalker babble noise at two different signal to noise ratios in order to mimic noisy environments. The data was collected from a total of 21 normal hearing subjects, who had always to detect a target syllable. It is concluded, that the WPSS is a robust measure to perceive differences between the effort needed to solve a task in an easy and a difficult listening condition. However, a further research will be to test hearing impaired persons to prove, if this electrophysiological method could be applied to improve the hearing aid fitting procedures in clinical settings.
    @InProceedings{bernea2010,
      author    = {Bernarding, C. and Corona-Strauss, F. I. and Latzel, M. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Auditory Streaming and Listening Effort: An Event-Related Potential Study},
      year      = {2010},
      pages     = {6817-6820},
      volume    = {2010:1},
      abstract  = {Until now, an objective method to estimate listening effort with a minimum level of cooperation of the patient in order to fit hearing aids is not existent. The benefit of such a method would be to reduce the listening effort in hearing impaired persons by an adequate adaption of the hearing aids. Recently, we have shown that the wavelet phase synchronization stability (WPSS) of auditory late responses could serve as a measure to estimate listening effort. In this paper, we extend our previous studies by using for the first time syllable stimulation paradigms with two levels of difficulty due to the combination of the syllables. Furthermore, by taking the model of auditory stream selection into account, the complexity of the paradigms was enhanced by the generation of a second competing auditory stream beside the syllable stream. This stream consisted of multitalker babble noise at two different signal to noise ratios in order to mimic noisy environments. The data was collected from a total of 21 normal hearing subjects, who had always to detect a target syllable. It is concluded, that the WPSS is a robust measure to perceive differences between the effort needed to solve a task in an easy and a difficult listening condition. However, a further research will be to test hearing impaired persons to prove, if this electrophysiological method could be applied to improve the hearing aid fitting procedures in clinical settings.},
      doi       = {10.1109/iembs.2010.5625957},
    }
  • C. Bernarding, D. J. Strauss, M. Latzel, and F. I. Corona-Strauss, "Non-Listening Effort Related Parameters in Auditory Discrimination Paradigms," in Conf Proc IEEE Eng Med Biol Soc, 2010, pp. 6682-6685. doi:10.1109/iembs.2010.5626265
    [BibTeX] [Abstract]
    Objective methods to asses listening effort are still missing in clinical settings. Thus, the focus of our ongoing research is the extraction of possible substrates of listening effort. This paper focuses on the non-effort related factor reaction time (RT) on the different components of auditory late responses (ALRs). It makes sense to consider this factor in the context of age related changes of the RT. For the comparison of the ALR components and the RT, two syllable oddball paradigms with different degree of difficulty were created. The paradigms were embedded in multitalker babble noise to create a realistic listening situation. The data was collected from 13 normal hearing healthy subjects, who had to detect a deviant. Furthermore, the wavelet phase synchronization stability (WPSS) was calculated for different scales. A filter bank was designed in order to separate the components by their frequency content. Finally, the Pearson product-moment correlation coefficient was calculated to clarify if there is a possible linkage between the RT and the ALR components. The results show, that only the P3 latency is correlated with the RT. A relation between the RT and the other ALR components could not be observed. It is concluded, that the focus of our further research, will be on the N1 and the P2 wave due to the fact that those components are independent from the non-effort related factor reaction time.
    @InProceedings{bernea2010b,
      author    = {Bernarding, C. and Strauss, D. J. and Latzel, M. and Corona-Strauss, F. I.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Non-Listening Effort Related Parameters in Auditory Discrimination Paradigms},
      year      = {2010},
      pages     = {6682-6685},
      volume    = {2010:1},
      abstract  = {Objective methods to asses listening effort are still missing in clinical settings. Thus, the focus of our ongoing research is the extraction of possible substrates of listening effort. This paper focuses on the non-effort related factor reaction time (RT) on the different components of auditory late responses (ALRs). It makes sense to consider this factor in the context of age related changes of the RT. For the comparison of the ALR components and the RT, two syllable oddball paradigms with different degree of difficulty were created. The paradigms were embedded in multitalker babble noise to create a realistic listening situation. The data was collected from 13 normal hearing healthy subjects, who had to detect a deviant. Furthermore, the wavelet phase synchronization stability (WPSS) was calculated for different scales. A filter bank was designed in order to separate the components by their frequency content. Finally, the Pearson product-moment correlation coefficient was calculated to clarify if there is a possible linkage between the RT and the ALR components. The results show, that only the P3 latency is correlated with the RT. A relation between the RT and the other ALR components could not be observed. It is concluded, that the focus of our further research, will be on the N1 and the P2 wave due to the fact that those components are independent from the non-effort related factor reaction time.},
      doi       = {10.1109/iembs.2010.5626265},
    }
  • F. I. Corona-Strauss, W. Delb, B. Schick, and D. J. Strauss, "A Kernel-Based Novelty Detection Scheme for the Ultra-fast detection of Chirp Evoked Auditory Brainstem Responses," in Conf Proc IEEE Eng Med Biol Soc, 2010, pp. 6833-6836. doi:10.1109/iembs.2010.5625950
    [BibTeX] [Abstract]
    Auditory Brainstem Responses (ABRs) are used as objective method for diagnostics and quantification of hearing loss. Many methods for automatic recognition of ABRs have been developed, but none of them include the individual measurement setup in the analysis. The purpose of this work was to design a fast recognition scheme for chirp-evoked ABRs that is adjusted to the individual measurement condition using spontaneous electroencephalographic activity (SA). For the classification, the kernel-based novelty detection scheme used features based on the inter-sweep instantaneous phase synchronization as well as energy and entropy relations in the time-frequency domain. This method provided SA discrimination from stimulations above the hearing threshold with a minimum number of sweeps, i.e., 200 individual responses. It is concluded that the proposed paradigm, processing procedures and stimulation techniques improve the detection of ABRs in terms of the degree of objectivity, i.e., automation of procedure, and measurement time.
    @InProceedings{coroea2010,
      author    = {Corona-Strauss, F. I. and Delb, W. and Schick, B. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {A Kernel-Based Novelty Detection Scheme for the Ultra-fast detection of Chirp Evoked Auditory Brainstem Responses},
      year      = {2010},
      pages     = {6833-6836},
      volume    = {2010:1},
      abstract  = {Auditory Brainstem Responses (ABRs) are used as objective method for diagnostics and quantification of hearing loss. Many methods for automatic recognition of ABRs have been developed, but none of them include the individual measurement setup in the analysis. The purpose of this work was to design a fast recognition scheme for chirp-evoked ABRs that is adjusted to the individual measurement condition using spontaneous electroencephalographic activity (SA). For the classification, the kernel-based novelty detection scheme used features based on the inter-sweep instantaneous phase synchronization as well as energy and entropy relations in the time-frequency domain. This method provided SA discrimination from stimulations above the hearing threshold with a minimum number of sweeps, i.e., 200 individual responses. It is concluded that the proposed paradigm, processing procedures and stimulation techniques improve the detection of ABRs in terms of the degree of objectivity, i.e., automation of procedure, and measurement time.},
      doi       = {10.1109/iembs.2010.5625950},
    }
  • K. Kern, V. Royter, F. I. Corona-Strauss, M. Mariam, and D. J. Strauss, "Habituation Analysis of Chirp vs. Tone Evoked Auditory Late Responses," in Conf Proc IEEE Eng Med Biol Soc, 2010, pp. 6825-6828. doi:10.1109/iembs.2010.5625954
    [BibTeX] [Abstract]
    We have recently shown that tone evoked auditory late responses are able to proof that habituation is occurring [1], [2]. The sweep to sweep analysis using time scale coherence method from [1] is used. Where clear results using tone evoked ALRs were obtained. Now it is of interest how does the results behave using chirp evoked ALRs compared to tone evoked ALRs so that basilar membrane dispersion is compensated. We presented three different tone bursts and three different band limited chirps to 10 subjects using two different loudness levels which the subjects determined themselves before as medium and uncomfortably loud. The 3 chirps are band limited within 3 different ranges, the chirp with the lowest center frequency has the smallest range (according to octave-band). Chirps and tone bursts are using the same center frequencies. We observed statistical clear results for the high frequency chirps. So we calculated a new chirp with the range of the high frequency chirp shifted to a smaller center frequency. After shifting the range to a lower frequency results tend to be more efficient. We have illustrated that habituation effect can also be seen using chirp stimuli. It could not unambiguously be clarified which role the bandwidth, the duration and the pitch of the chirps are playing in general.
    @InProceedings{kernea2010,
      author    = {Kern, K. and Royter, V. and Corona-Strauss, F. I. and Mariam, M. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Habituation Analysis of Chirp vs. Tone Evoked Auditory Late Responses},
      year      = {2010},
      pages     = {6825-6828},
      volume    = {2010:1},
      abstract  = {We have recently shown that tone evoked auditory late responses are able to proof that habituation is occurring [1], [2]. The sweep to sweep analysis using time scale coherence method from [1] is used. Where clear results using tone evoked ALRs were obtained. Now it is of interest how does the results behave using chirp evoked ALRs compared to tone evoked ALRs so that basilar membrane dispersion is compensated. We presented three different tone bursts and three different band limited chirps to 10 subjects using two different loudness levels which the subjects determined themselves before as medium and uncomfortably loud. The 3 chirps are band limited within 3 different ranges, the chirp with the lowest center frequency has the smallest range (according to octave-band). Chirps and tone bursts are using the same center frequencies. We observed statistical clear results for the high frequency chirps. So we calculated a new chirp with the range of the high frequency chirp shifted to a smaller center frequency. After shifting the range to a lower frequency results tend to be more efficient. We have illustrated that habituation effect can also be seen using chirp stimuli. It could not unambiguously be clarified which role the bandwidth, the duration and the pitch of the chirps are playing in general.},
      doi       = {10.1109/iembs.2010.5625954},
    }

2009

  • F. I. Corona-Strauss, W. Delb, B. Schick, and D. J. Strauss, "Phase Stability Analysis of Chirp Evoked Auditory Brainstem Responses by Gabor Frame Operators," IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 17, iss. 6, pp. 530-536, 2009. doi:10.1109/tnsre.2009.2032627
    [BibTeX] [Abstract]
    We have recently shown that click evoked auditory brainstem responses (ABRs) can be efficiently processed using a novelty detection paradigm. Here, ABRs as a large-scale reflection of a stimulus locked neuronal group synchronization at the brainstem level are detected as novel instance-novel as compared to the spontaneous activity which does not exhibit a regular stimulus locked synchronization. In this paper we propose for the first time Gabor frame operators as an efficient feature extraction technique for ABR single sweep sequences that is in line with this paradigm. In particular, we use this decomposition technique to derive the Gabor frame phase stability (GFPS) of sweep sequences of click and chirp evoked ABRs. We show that the GFPS of chirp evoked ABRs provides a stable discrimination of the spontaneous activity from stimulations above the hearing threshold with a small number of sweeps, even at low stimulation intensities. It is concluded that the GFPS analysis represents a robust feature extraction method for ABR single sweep sequences. Further studies are necessary to evaluate the value of the presented approach for clinical applications.
    @Article{coroea2009,
      author    = {Corona-Strauss, F. I. and Delb, W. and Schick, B. and Daniel J. Strauss},
      journal   = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
      title     = {Phase Stability Analysis of Chirp Evoked Auditory Brainstem Responses by Gabor Frame Operators},
      year      = {2009},
      month     = {dec},
      number    = {6},
      pages     = {530-536},
      volume    = {17},
      abstract  = {We have recently shown that click evoked auditory brainstem responses (ABRs) can be efficiently processed using a novelty detection paradigm. Here, ABRs as a large-scale reflection of a stimulus locked neuronal group synchronization at the brainstem level are detected as novel instance-novel as compared to the spontaneous activity which does not exhibit a regular stimulus locked synchronization. In this paper we propose for the first time Gabor frame operators as an efficient feature extraction technique for ABR single sweep sequences that is in line with this paradigm. In particular, we use this decomposition technique to derive the Gabor frame phase stability (GFPS) of sweep sequences of click and chirp evoked ABRs. We show that the GFPS of chirp evoked ABRs provides a stable discrimination of the spontaneous activity from stimulations above the hearing threshold with a small number of sweeps, even at low stimulation intensities. It is concluded that the GFPS analysis represents a robust feature extraction method for ABR single sweep sequences. Further studies are necessary to evaluate the value of the presented approach for clinical applications.},
      doi       = {10.1109/tnsre.2009.2032627},
      keywords  = {Auditory brainstem responses (ABRs),Chirp stimulation,Filter banks,Gabor frames,Phase synchronization},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • Y. F. Low and D. J. Strauss, "EEG phase reset due to auditory attention: an inverse time-scale approach," Physiological Measurement, vol. 30, iss. 8, pp. 821-832, 2009. doi:10.1088/0967-3334/30/8/007
    [BibTeX] [Abstract]
    We propose a novel tool to evaluate the electroencephalograph (EEG) phase reset due to auditory attention by utilizing an inverse analysis of the instantaneous phase for the first time. EEGs were acquired through auditory attention experiments with a maximum entropy stimulation paradigm. We examined single sweeps of auditory late response (ALR) with the complex continuous wavelet transform. The phase in the frequency band that is associated with auditory attention (6-10 Hz, termed as theta-alpha border) was reset to the mean phase of the averaged EEGs. The inverse transform was applied to reconstruct the phase-modified signal. We found significant enhancement of the N100 wave in the reconstructed signal. Analysis of the phase noise shows the effects of phase jittering on the generation of the N100 wave implying that a preferred phase is necessary to generate the event-related potential (ERP). Power spectrum analysis shows a remarkable increase of evoked power but little change of total power after stabilizing the phase of EEGs. Furthermore, by resetting the phase only at the theta border of no attention data to the mean phase of attention data yields a result that resembles attention data. These results show strong connections between EEGs and ERP, in particular, we suggest that the presentation of an auditory stimulus triggers the phase reset process at the theta-alpha border which leads to the emergence of the N100 wave. It is concluded that our study reinforces other studies on the importance of the EEG in ERP genesis.
    @Article{lowea2009,
      author    = {Low, Y. F. and Strauss, D. J.},
      journal   = {Physiological Measurement},
      title     = {EEG phase reset due to auditory attention: an inverse time-scale approach},
      year      = {2009},
      month     = {jun},
      number    = {8},
      pages     = {821-832},
      volume    = {30},
      abstract  = {We propose a novel tool to evaluate the electroencephalograph (EEG) phase reset due to auditory attention by utilizing an inverse analysis of the instantaneous phase for the first time. EEGs were acquired through auditory attention experiments with a maximum entropy stimulation paradigm. We examined single sweeps of auditory late response (ALR) with the complex continuous wavelet transform. The phase in the frequency band that is associated with auditory attention (6-10 Hz, termed as theta-alpha border) was reset to the mean phase of the averaged EEGs. The inverse transform was applied to reconstruct the phase-modified signal. We found significant enhancement of the N100 wave in the reconstructed signal. Analysis of the phase noise shows the effects of phase jittering on the generation of the N100 wave implying that a preferred phase is necessary to generate the event-related potential (ERP). Power spectrum analysis shows a remarkable increase of evoked power but little change of total power after stabilizing the phase of EEGs. Furthermore, by resetting the phase only at the theta border of no attention data to the mean phase of attention data yields a result that resembles attention data. These results show strong connections between EEGs and ERP, in particular, we suggest that the presentation of an auditory stimulus triggers the phase reset process at the theta-alpha border which leads to the emergence of the N100 wave. It is concluded that our study reinforces other studies on the importance of the EEG in ERP genesis.},
      doi       = {10.1088/0967-3334/30/8/007},
      keywords  = {Auditory attention,EEG phase reset,Inverse transform,Time-scale,Wavelet phase stability},
      publisher = {{IOP} Publishing},
    }
  • M. Mariam, W. Delb, F. I. Corona-Strauss, M. Bloching, and D. J. Strauss, "Comparing the Habituation of the Late Auditory Potentials to Loud and Soft Sounds," Physiological Measurement, vol. 30, iss. 2, pp. 141-153, 2009. doi:10.1088/0967-3334/30/2/003
    [BibTeX] [Abstract]
    The objective fitting of hearing aids and cochlear implants remains a challenge. In particular, the determination of whether sound is perceived as too loud or comfortable represents an unsolved problem in noncooperative patients. In a first step of an ongoing study, we assess the feasibility of habituation correlates in late auditory evoked potentials (LAEPs) to discriminate between a soft sound (SS) of 50 dB SPL and a loud sound (LS) of 100 dB SPL. We applied a new sweep-to-sweep time-scale coherence measure to analyse the habituation in LAEPs, i.e., relative changes within sweep sequences. From the comparison between both stimulation levels, a total discrimination of responses to SS and LS in the individual normal hearing subject was possible. As just relative changes in SS and LS sweep sequences were considered, purely exogenously driven morphological alternations in the responses such as intensity related amplitude and latency changes were excluded from the analysis. It is concluded that the proposed method allows for the reliable detection of auditory habituation and differentiation of SS from LS. The proposed scheme might provide an electrophysiological measurement and signal processing framework for the objective detection of the most comfortable loudness level and can be used in further, more clinically oriented studies.
    @Article{mariea2009,
      author    = {Mariam, M. and Delb, W. and Corona-Strauss, F. I. and Bloching, M. and Strauss, D. J.},
      journal   = {Physiological Measurement},
      title     = {Comparing the Habituation of the Late Auditory Potentials to Loud and Soft Sounds},
      year      = {2009},
      month     = {jan},
      number    = {2},
      pages     = {141-153},
      volume    = {30},
      abstract  = {The objective fitting of hearing aids and cochlear implants remains a challenge. In particular, the determination of whether sound is perceived as too loud or comfortable represents an unsolved problem in noncooperative patients. In a first step of an ongoing study, we assess the feasibility of habituation correlates in late auditory evoked potentials (LAEPs) to discriminate between a soft sound (SS) of 50 dB SPL and a loud sound (LS) of 100 dB SPL. We applied a new sweep-to-sweep time-scale coherence measure to analyse the habituation in LAEPs, i.e., relative changes within sweep sequences. From the comparison between both stimulation levels, a total discrimination of responses to SS and LS in the individual normal hearing subject was possible. As just relative changes in SS and LS sweep sequences were considered, purely exogenously driven morphological alternations in the responses such as intensity related amplitude and latency changes were excluded from the analysis. It is concluded that the proposed method allows for the reliable detection of auditory habituation and differentiation of SS from LS. The proposed scheme might provide an electrophysiological measurement and signal processing framework for the objective detection of the most comfortable loudness level and can be used in further, more clinically oriented studies.},
      doi       = {10.1088/0967-3334/30/2/003},
      keywords  = {Habituation,Wavelets,auditory evoked potentials,cochlear implants,hearing aids,uncomfortable loudness},
      publisher = {{IOP} Publishing},
    }
  • C. Trenado, L. Haab, W. Reith, and D. J. Strauss, "Biocybernetics of attention in the tinnitus decompensation: An integrative multiscale modeling approach," Journal of Neuroscience Methods, vol. 178, iss. 1, pp. 237-47, 2009. doi:10.1016/j.jneumeth.2008.12.012
    [BibTeX] [Abstract]
    Tinnitus is one of the most common symptoms affecting people all over the world. In the absence of an established cure many individuals are not only faced with the need to adjust to the sensation of the tinnitus noise, but also with psychological comorbidities. In recent years, different studies have been directed to elucidate the psychophysiological mechanisms that are involved in the tinnitus decompensation. From these, special emphasis has been placed on studies related to attention and habituation, which accordingly play a crucial role in current tinnitus therapy approaches. In spite of such progress, the relationship between selective attention and the tinnitus decompensation with respect to large-scale neural correlates is still not well understood. In order to address this issue, we propose an integrative multiscale modeling approach for studying neural correlates of auditory selective attention in the tinnitus decompensation. Computational simulations based on our model confirmed electroencephalographic human data of both auditory selective attention and the tinnitus decompensation. It is concluded that the proposed methodology represents a promising approach to give insight into the neurodynamics of auditory selective attention in the tinnitus decompensation.
    @Article{trenea2009,
      author    = {Trenado, C. and Haab, L. and Reith, W. and Strauss, D. J.},
      journal   = {Journal of Neuroscience Methods},
      title     = {Biocybernetics of attention in the tinnitus decompensation: An integrative multiscale modeling approach},
      year      = {2009},
      month     = {mar},
      number    = {1},
      pages     = {237-47},
      volume    = {178},
      abstract  = {Tinnitus is one of the most common symptoms affecting people all over the world. In the absence of an established cure many individuals are not only faced with the need to adjust to the sensation of the tinnitus noise, but also with psychological comorbidities. In recent years, different studies have been directed to elucidate the psychophysiological mechanisms that are involved in the tinnitus decompensation. From these, special emphasis has been placed on studies related to attention and habituation, which accordingly play a crucial role in current tinnitus therapy approaches. In spite of such progress, the relationship between selective attention and the tinnitus decompensation with respect to large-scale neural correlates is still not well understood. In order to address this issue, we propose an integrative multiscale modeling approach for studying neural correlates of auditory selective attention in the tinnitus decompensation. Computational simulations based on our model confirmed electroencephalographic human data of both auditory selective attention and the tinnitus decompensation. It is concluded that the proposed methodology represents a promising approach to give insight into the neurodynamics of auditory selective attention in the tinnitus decompensation.},
      doi       = {10.1016/j.jneumeth.2008.12.012},
      keywords  = {Auditory evoked cortical potentials,Auditory scene analysis,Auditory selective attention,Multiscale modeling,Tinnitus decompensation},
      publisher = {Elsevier {BV}},
    }
  • C. Trenado, L. Haab, and D. J. Strauss, "Corticothalamic Feedback Dynamics for Neural Correlates of Auditory Selective Attention," IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 17, iss. 1, pp. 46-52, 2009. doi:10.1109/tnsre.2008.2010469
    [BibTeX] [Abstract]
    Auditory evoked cortical potentials (AECPs) have been consolidated as a diagnostic tool in audiology. Further applications of this technique are in experimental neuropsychology, neuroscience, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation. In particular, numerous psychophysiological studies have emphasized their dynamic characteristics in relation to exogenous and endogenous attention. However, the effect of corticothalamic feedback dynamics to neural correlates of focal and nonfocal attention and its large-scale effect reflected in AECPs is far from being understood. To address this issue, we model neural correlates of auditory selective attention reflected in AECPs by using corticothalamic feedback dynamics. In our framework, we make use of a well-known multiscale model of evoked potentials, for which we define for the first time a neurofunctional map of relevant corticothalamic loops to the hearing path. Such loops are in turn are coupled to our proposed probabilistic scheme of auditory selective attention. It is concluded that our model represents a promising approach to gain a deeper understanding of the neurodynamics of auditory attention and might be used as an efficient forward model to support hypotheses that are obtained in experimental paradigms involving AECPs.
    @Article{trenea2009c,
      author    = {Trenado, C. and Haab, L. and Strauss, D. J.},
      journal   = {{IEEE} Transactions on Neural Systems and Rehabilitation Engineering},
      title     = {Corticothalamic Feedback Dynamics for Neural Correlates of Auditory Selective Attention},
      year      = {2009},
      month     = {feb},
      number    = {1},
      pages     = {46-52},
      volume    = {17},
      abstract  = {Auditory evoked cortical potentials (AECPs) have been consolidated as a diagnostic tool in audiology. Further applications of this technique are in experimental neuropsychology, neuroscience, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation. In particular, numerous psychophysiological studies have emphasized their dynamic characteristics in relation to exogenous and endogenous attention. However, the effect of corticothalamic feedback dynamics to neural correlates of focal and nonfocal attention and its large-scale effect reflected in AECPs is far from being understood. To address this issue, we model neural correlates of auditory selective attention reflected in AECPs by using corticothalamic feedback dynamics. In our framework, we make use of a well-known multiscale model of evoked potentials, for which we define for the first time a neurofunctional map of relevant corticothalamic loops to the hearing path. Such loops are in turn are coupled to our proposed probabilistic scheme of auditory selective attention. It is concluded that our model represents a promising approach to gain a deeper understanding of the neurodynamics of auditory attention and might be used as an efficient forward model to support hypotheses that are obtained in experimental paradigms involving AECPs.},
      doi       = {10.1109/tnsre.2008.2010469},
      keywords  = {Auditory selective attention,Corticothalamic feedback,Evoked potentials,Probabilistic model,Single trials processing,Top-down processing},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • M. Busse, L. Haab, M. Mariam, C. Crick, T. Weis, W. Reith, and D. J. Strauss, "Assessment of Aversive Stimuli Dependent Attentional Binding by the N170 VEP Component," in Conf Proc IEEE Eng Med Biol Soc, 2009. doi:10.1109/iembs.2009.5333647
    [BibTeX] [Abstract]
    For social species nonverbal communication by assessment of emotion expression is crucial for building up and maintaining social structures. In humans, body language not only includes gestures but also a variety of facial expressions. Negative associated facial expressions, e.g. disgust, fear, anger call for a higher attentional binding due their evolutionary background, denoting directly personal dangers for the receptive individual. In a number of psychiatric disorders such as schizophrenia or autism spectrum diseases, the assessment of emotions in faces is disturbed, leading to even more pronounced social cuts. In this article we present a new methodology for monitoring the attentional binding to emotion-tinged stimuli in a face recognition task. We were able to demonstrate a significant difference in habituation behavior to neutral and negative associated faces respectively. In future, this methodology might provide a fast and reliable scheme for the detection of psychiatric disorders comprising dysfunction of limbic structures.
    @InProceedings{bussea2009,
      author    = {Busse, M. and Haab, L. and Mariam, M. and Crick, C. and Weis, T. and Reith, W. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Assessment of Aversive Stimuli Dependent Attentional Binding by the N170 VEP Component},
      year      = {2009},
      volume    = {2009:1},
      abstract  = {For social species nonverbal communication by assessment of emotion expression is crucial for building up and maintaining social structures. In humans, body language not only includes gestures but also a variety of facial expressions. Negative associated facial expressions, e.g. disgust, fear, anger call for a higher attentional binding due their evolutionary background, denoting directly personal dangers for the receptive individual. In a number of psychiatric disorders such as schizophrenia or autism spectrum diseases, the assessment of emotions in faces is disturbed, leading to even more pronounced social cuts. In this article we present a new methodology for monitoring the attentional binding to emotion-tinged stimuli in a face recognition task. We were able to demonstrate a significant difference in habituation behavior to neutral and negative associated faces respectively. In future, this methodology might provide a fast and reliable scheme for the detection of psychiatric disorders comprising dysfunction of limbic structures.},
      doi       = {10.1109/iembs.2009.5333647},
    }
  • F. I. Corona-Strauss, D. J. Strauss, B. Schick, and W. Delb, "A series of notched-noise embedded chirps for objective frequency specific hearing examinations," in Conf Proc IEEE Eng Med Biol Soc, 2009, pp. 2074-2077. doi:10.1109/iembs.2009.5333955
    [BibTeX]
    @InProceedings{coroea2009,
      author    = {Corona-Strauss, F. I. and Strauss, D. J. and Schick, B. and Delb, W.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {A series of notched-noise embedded chirps for objective frequency specific hearing examinations},
      year      = {2009},
      pages     = {2074-2077},
      doi       = {10.1109/iembs.2009.5333955},
    }
  • F. I. Corona-Strauss, W. Delb, B. Schick, S. Hussain, and D. J. Strauss, "Gabor Frame Phase Stability Analysis of Chirp Evoked Auditory Brainstem Responses," in Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on, 2009, pp. 730-733. doi:10.1109/ner.2009.5109400
    [BibTeX]
    @InProceedings{coroea2009b,
      author    = {Corona-Strauss, F. I. and Delb, W. and Schick, B. and Hussain, S. and Strauss, D. J.},
      booktitle = {Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on},
      title     = {Gabor Frame Phase Stability Analysis of Chirp Evoked Auditory Brainstem Responses},
      year      = {2009},
      pages     = {730-733},
      doi       = {10.1109/ner.2009.5109400},
    }
  • L. Haab, E. Wallhäusser-Franke, C. Trenado, and D. J. Strauss, "Modeling Limbic Influences on Habituation Deficits in Chronic Tinnitus Aurium," in Conf Proc IEEE Eng Med Biol Soc, 2009, pp. 4234-4237. doi:10.1109/iembs.2009.5332696
    [BibTeX] [Abstract]
    About 93% of healthy subjects suffer from tinnitus-like symptoms when deprived of auditory stimuli, e.g., in a sound-proof chamber. This suggests an underlying physiological mechanism causing auditory sensations during absence of an external sound source. Grossberg suggested a mechanism by which hallucinations arise from mechanisms of learning, attention and volition. According to this mechanism notch-like hearing deficits are sufficient for experiencing auditory hallucinations, while their chronification is attributed to reorganization processes. In tinnitus sufferers the auditory sensation is accompanied by the inability to habituate to this endogenous sound. This disability might originate from a coactivation of brain areas that are only indirectly involved in cognitive processing such as areas belonging to the limbic system. Moreover subjective loudness of the tinnitus sensation is likely to depend on the amount of selective attention assigned to the tinnitus stream. Here we propose a functional model of pure-tone tinnitus in which exogenous and endogenous input into processing modules is represented as streams. We model the selection of the tinnitus stream at the subthalamic level according to its weighting. Then we propose a mechanism for the inability to habituate to this stream due to limbic coactivation and amplification by mechanisms of attentional guidance, and by the influence corticofugal projections on lower auditory processing stages. The model is able to replicate the phase stability of auditory evoked potentials as seen in tinnitus sufferers and controls.
    @InProceedings{haabea2009,
      author    = {Haab, L. and Wallh\"{a}usser-Franke, E. and Trenado, C. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Modeling Limbic Influences on Habituation Deficits in Chronic Tinnitus Aurium},
      year      = {2009},
      pages     = {4234-4237},
      volume    = {2009:1},
      abstract  = {About 93% of healthy subjects suffer from tinnitus-like symptoms when deprived of auditory stimuli, e.g., in a sound-proof chamber. This suggests an underlying physiological mechanism causing auditory sensations during absence of an external sound source. Grossberg suggested a mechanism by which hallucinations arise from mechanisms of learning, attention and volition. According to this mechanism notch-like hearing deficits are sufficient for experiencing auditory hallucinations, while their chronification is attributed to reorganization processes. In tinnitus sufferers the auditory sensation is accompanied by the inability to habituate to this endogenous sound. This disability might originate from a coactivation of brain areas that are only indirectly involved in cognitive processing such as areas belonging to the limbic system. Moreover subjective loudness of the tinnitus sensation is likely to depend on the amount of selective attention assigned to the tinnitus stream. Here we propose a functional model of pure-tone tinnitus in which exogenous and endogenous input into processing modules is represented as streams. We model the selection of the tinnitus stream at the subthalamic level according to its weighting. Then we propose a mechanism for the inability to habituate to this stream due to limbic coactivation and amplification by mechanisms of attentional guidance, and by the influence corticofugal projections on lower auditory processing stages. The model is able to replicate the phase stability of auditory evoked potentials as seen in tinnitus sufferers and controls.},
      doi       = {10.1109/iembs.2009.5332696},
    }
  • Y. F. Low, K. Schwerdtfeger, A. R. Harris, and D. J. Strauss, "An Investigation on The Effects of Single Pulse Transcranial Magnetic Stimulation in A Modified Maximum Entropy Auditory Stimulation Paradigm," in Conf Proc IEEE Eng Med Biol Soc, 2009. doi:10.1109/iembs.2009.5334066
    [BibTeX]
    @InProceedings{lowea2009,
      author    = {Low, Y. F. and Schwerdtfeger, K. and Harris, A. R. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {An Investigation on The Effects of Single Pulse Transcranial Magnetic Stimulation in A Modified Maximum Entropy Auditory Stimulation Paradigm},
      year      = {2009},
      volume    = {2009:1},
      doi       = {10.1109/iembs.2009.5334066},
    }
  • M. Mariam, W. Delb, and D. J. Strauss, "Differentiation of Perceived Sound Levels by Electroencephalographic Data: A Novelty Detection Approach Using Habituation Correlates," in Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on, 2009, pp. 570-573. doi:10.1109/ner.2009.5109360
    [BibTeX] [Abstract]
    Unsolved problem of cochlear implant as well as hearing aid fitting, i.e., to determine the threshold of most comfortable loudness level motivated our study. In the present study, we apply a single-sweep processing method which employs a hybrid approach of adaptive frame decomposition and the kernel based novelty detection machine for the detection of auditory habituation in late auditory evoked potentials (LAEPs) to differentiate the sweeps at 60dB sound pressure level (SPL), 70dB SPL, 80dB SPL, and 90dB SPL stimulation level. A significance difference among the habituation correlates in LAEPs of these stimulation levels was observed. It is concluded that the new approach provides a reliable method in the detection of habituation as well as differentiation of stimulation levels. It can be further used in more clinically oriented studies related to an objective fitting of hearing aids or cochlear implants.
    @InProceedings{mariea2009b,
      author    = {Mariam, M. and Delb, W. and Strauss, D. J.},
      booktitle = {Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on},
      title     = {Differentiation of Perceived Sound Levels by Electroencephalographic Data: A Novelty Detection Approach Using Habituation Correlates},
      year      = {2009},
      pages     = {570-573},
      volume    = {2009:1},
      abstract  = {Unsolved problem of cochlear implant as well as hearing aid fitting, i.e., to determine the threshold of most comfortable loudness level motivated our study. In the present study, we apply a single-sweep processing method which employs a hybrid approach of adaptive frame decomposition and the kernel based novelty detection machine for the detection of auditory habituation in late auditory evoked potentials (LAEPs) to differentiate the sweeps at 60dB sound pressure level (SPL), 70dB SPL, 80dB SPL, and 90dB SPL stimulation level. A significance difference among the habituation correlates in LAEPs of these stimulation levels was observed. It is concluded that the new approach provides a reliable method in the detection of habituation as well as differentiation of stimulation levels. It can be further used in more clinically oriented studies related to an objective fitting of hearing aids or cochlear implants.},
      doi       = {10.1109/ner.2009.5109360},
    }
  • I. Mustaffa, C. Trenado, H. Rahim, and D. J. Strauss, "Sharpening of neurite morphology using complex coherence enhanced diffusion," in Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on, 2009, pp. 3593-3596. doi:10.1109/iembs.2009.5333152
    [BibTeX] [Abstract]
    The study of the molecular mechanisms involved in neurite outgrowth and differentiation, requires essential accurate and reproducible segmentation and quantification of neuronal processes. The common method used in this study is to detect and trace individual neurites, i.e. neurite tracing. The challenge comes mainly from the morphological problem in which these images contains ambiguities such as neurites discontinuities and intensity differences. In our work, we encounter a bigger challenge as the neurites in our images have a higher density of neurites. In this paper, we present a hybrid complex coherence-enhanced method for sharpening the morphology of neurons from such images. Coherence-enhanced diffusion (CED) is used to enhance the flowlike structures of the neurites, while the imaginary part of the complex nonlinear diffusion of the image cancels the appearance of 'clouds'. We also describe an elementary method for estimating the density of neuritis based on the obtained images. Our preliminary results show that the proposed methodology is a step ahead toward an effective neuronal morphology algorithm.
    @InProceedings{mustea2009,
      author    = {Mustaffa, I. and Trenado, C. and Rahim, H. and Strauss, D. J.},
      booktitle = {Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on},
      title     = {Sharpening of neurite morphology using complex coherence enhanced diffusion},
      year      = {2009},
      pages     = {3593-3596},
      abstract  = {The study of the molecular mechanisms involved in neurite outgrowth and differentiation, requires essential accurate and reproducible segmentation and quantification of neuronal processes. The common method used in this study is to detect and trace individual neurites, i.e. neurite tracing. The challenge comes mainly from the morphological problem in which these images contains ambiguities such as neurites discontinuities and intensity differences. In our work, we encounter a bigger challenge as the neurites in our images have a higher density of neurites. In this paper, we present a hybrid complex coherence-enhanced method for sharpening the morphology of neurons from such images. Coherence-enhanced diffusion (CED) is used to enhance the flowlike structures of the neurites, while the imaginary part of the complex nonlinear diffusion of the image cancels the appearance of 'clouds'. We also describe an elementary method for estimating the density of neuritis based on the obtained images. Our preliminary results show that the proposed methodology is a step ahead toward an effective neuronal morphology algorithm.},
      doi       = {10.1109/iembs.2009.5333152},
    }
  • D. J. Strauss, F. I. Corona-Strauss, C. Bernarding, M. Latzel, and M. Froehlich, "On the cognitive neurodynamics of listening effort: A phase clustering analysis of large-scale neural correlates," in Conf Proc IEEE Eng Med Biol Soc, 2009, pp. 2078-2081. doi:10.1109/iembs.2009.5333956
    [BibTeX] [Abstract]
    An increased listening effort represents a major problem in humans with hearing impairment. Neurodiagnostic methods for an objective listening effort estimation could revolutionize auditory rehabilitation. However the cognitive neurodynamics of listening effort is not understood and research related its neural correlates is still in its infancy. In this paper we present a phase clustering analysis of large-scale listening effort correlates in auditory late responses (ALRs). For this we apply the complex wavelet transform as well as tight Gabor Frame (TGF) operators. We show (a) that phase clustering on the unit circle can separate ALR data from auditory paradigms which require a graduated effort for their solution; (b) the application of TGFs for an inverse artificial phase stabilization at the $\alpha$/$\theta$-border enlarges the endogenously driven listening effort correlates in the reconstructed time-domain waveforms. It is concluded that listening effort correlates can be extracted from ALR sequences using an instantaneous phase clustering analysis, at least by means of the applied experimental pure tone paradigm.
    @InProceedings{straea2009,
      author    = {Strauss, D. J. and Corona-Strauss, F. I. and Bernarding, C. and Latzel, M. and Froehlich, M.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {On the cognitive neurodynamics of listening effort: A phase clustering analysis of large-scale neural correlates},
      year      = {2009},
      pages     = {2078-2081},
      abstract  = {An increased listening effort represents a major problem in humans with hearing impairment. Neurodiagnostic methods for an objective listening effort estimation could revolutionize auditory rehabilitation. However the cognitive neurodynamics of listening effort is not understood and research related its neural correlates is still in its infancy. In this paper we present a phase clustering analysis of large-scale listening effort correlates in auditory late responses (ALRs). For this we apply the complex wavelet transform as well as tight Gabor Frame (TGF) operators. We show (a) that phase clustering on the unit circle can separate ALR data from auditory paradigms which require a graduated effort for their solution; (b) the application of TGFs for an inverse artificial phase stabilization at the $\alpha$/$\theta$-border enlarges the endogenously driven listening effort correlates in the reconstructed time-domain waveforms. It is concluded that listening effort correlates can be extracted from ALR sequences using an instantaneous phase clustering analysis, at least by means of the applied experimental pure tone paradigm.},
      doi       = {10.1109/iembs.2009.5333956},
    }
  • C. Trenado, L. Haab, W. Reith, and D. J. Strauss, "Toward a Realistic Simulation Framework for Large-Scale Neural Correlates in Clinical Applications," in Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on, 2009, pp. 199-202. doi:10.1109/ner.2009.5109268
    [BibTeX] [Abstract]
    Recent advances in neural engineering and mathematical methods influence more and more the way in which brain disorders and symptoms are being diagnosed and treated. In this direction, experimental findings, which emphasize on the correlation between large-scale neural correlates reflected in electroencephalographic data and neuronal mechanisms, have propelled the development of novel brain computer interfaces that represent a step ahead toward the realization of neural rehabilitation devices. In spite of this progress, a forward simulation framework that can reliably assist clinical studies in testing hypothesis related to neural correlates with respect to cognitive mechanisms and brain malfunctioning, is still in its infancy. To address this issue, we propose a cortico-subcortical simulation framework by means of the neural field approach. We show that this method allows for the consideration of relevant brain structures. We provide an instance in which our framework is successfully tested and discuss about a potential clinical application. It is concluded that our methodology represents a promising tool in assisting clinical studies for the treatment and diagnosis of brain disorders and studies concerning behavioral mechanisms.
    @InProceedings{trenea2009d,
      author    = {Trenado, C. and Haab, L. and Reith, W. and Strauss, D. J.},
      booktitle = {Neural Engineering, 2009. NER 09. 4th International IEEE/EMBS Conference on},
      title     = {Toward a Realistic Simulation Framework for Large-Scale Neural Correlates in Clinical Applications},
      year      = {2009},
      pages     = {199-202},
      volume    = {2009:1},
      abstract  = {Recent advances in neural engineering and mathematical methods influence more and more the way in which brain disorders and symptoms are being diagnosed and treated. In this direction, experimental findings, which emphasize on the correlation between large-scale neural correlates reflected in electroencephalographic data and neuronal mechanisms, have propelled the development of novel brain computer interfaces that represent a step ahead toward the realization of neural rehabilitation devices. In spite of this progress, a forward simulation framework that can reliably assist clinical studies in testing hypothesis related to neural correlates with respect to cognitive mechanisms and brain malfunctioning, is still in its infancy. To address this issue, we propose a cortico-subcortical simulation framework by means of the neural field approach. We show that this method allows for the consideration of relevant brain structures. We provide an instance in which our framework is successfully tested and discuss about a potential clinical application. It is concluded that our methodology represents a promising tool in assisting clinical studies for the treatment and diagnosis of brain disorders and studies concerning behavioral mechanisms.},
      doi       = {10.1109/ner.2009.5109268},
    }

2008

  • W. Delb, D. J. Strauss, Y. F. Low, H. Seidler, A. Rheinschmitt, T. Wobrock, and R. D'Amelio, "Alterations in Event Related Potentials (ERP) Associated with Tinnitus Distress and Attention," Applied Psychophysiology and Biofeedback, vol. 33, iss. 4, pp. 211-221, 2008. doi:10.1007/s10484-008-9065-y
    [BibTeX] [Abstract]
    Tinnitus related distress corresponds to different degrees of attention paid to the tinnitus. Shifting attention to a signal other than the tinnitus is therefore particularly difficult for patients with high tinnitus related distress. As attention effects on Event Related Potentials (ERP) have been shown this should be reflected in ERP measurements (N100, phase locking). In order to prove this hypothesis single sweep ERP recordings were obtained in 41 tinnitus patients as well as 10 control subjects during a period of time when attention was shifted to a tone (attended) and during a second phase (unattended) when they did not focus attention to the tone. Whereas tinnitus patients with low distress showed a significant reduction in both N100 amplitude and phase locking when comparing the attended and unattended measurement condition a group of patients with high tinnitus related distress did not show such ERP alterations. Using single sweep ERP measurements the results of our study show, that attention in high tinnitus related distress patients is captured by their tinnitus significantly more than in low distress patients. Furthermore our results provide the basis for future neurofeedback based tinnitus therapies aiming at maximizing the ability to shift attention away from the tinnitus.
    @Article{delbea2008,
      author    = {Delb, W. and Strauss, D. J. and Low, Y. F. and Seidler, H. and Rheinschmitt, A. and Wobrock, T. and D'Amelio, R.},
      journal   = {Applied Psychophysiology and Biofeedback},
      title     = {Alterations in Event Related Potentials (ERP) Associated with Tinnitus Distress and Attention},
      year      = {2008},
      month     = {oct},
      number    = {4},
      pages     = {211-221},
      volume    = {33},
      abstract  = {Tinnitus related distress corresponds to different degrees of attention paid to the tinnitus. Shifting attention to a signal other than the tinnitus is therefore particularly difficult for patients with high tinnitus related distress. As attention effects on Event Related Potentials (ERP) have been shown this should be reflected in ERP measurements (N100, phase locking). In order to prove this hypothesis single sweep ERP recordings were obtained in 41 tinnitus patients as well as 10 control subjects during a period of time when attention was shifted to a tone (attended) and during a second phase (unattended) when they did not focus attention to the tone. Whereas tinnitus patients with low distress showed a significant reduction in both N100 amplitude and phase locking when comparing the attended and unattended measurement condition a group of patients with high tinnitus related distress did not show such ERP alterations. Using single sweep ERP measurements the results of our study show, that attention in high tinnitus related distress patients is captured by their tinnitus significantly more than in low distress patients. Furthermore our results provide the basis for future neurofeedback based tinnitus therapies aiming at maximizing the ability to shift attention away from the tinnitus.},
      doi       = {10.1007/s10484-008-9065-y},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • M. Mariam, W. Delb, F. I. Corona-Strauss, M. Bloching, and D. J. Strauss, "Extraction of Habituation Correlates in Single Sweep Sequences of Late Auditory Evoked Potentials using Time-Scale Coherence: Objective Detection of Uncomfortable Loudness Level," BioMed Journal 2008, pp. 601-605, 2008.
    [BibTeX] [Abstract]
    The fitting of cochlear implants as well as hearing aids requires information on the hearing threshold as well as on the uncomfortable loudness level. Due to its very subjective nature, the estimation of the uncomfortable loudness level is particularly challenging and represents a clinically unsolved problem. Using a computational monitoring of the habituation processes in single sweeps recordings of late auditory evoked potentials (LAEP), we propose a method that might be able to objectively determine the uncomfortable loudness level in non-cooperative patients such as newborns. Here we presented preliminary results of an ongoing study. Single sweep recordings of LAEP were performed at 2 stimulation levels, 50dB and and lOOdB hearing level (HL) with an interstimulus interval (ISI) of Is. In a group of 10 voluntary adult subjects with normal hearing, our scheme based on the analysis of single sweeps recordings and the calculation of time-scale phase coherence, the 1.12% reduction of time-scale phase coherence index for 50dB HL and 0.30% for lOOdB HL were observed. Therefore, habituation of 50dB HL stimulus had successfully been detected and no significant difference in sweeps evolution for 100dB HL stimulus (Wilcoxon test, significance level p <0.05). It is concluded that the proposed method possibly allows for the reliable detection of habituation and differentiation of comfortable from uncomfortable loudness levels in cochlear implants and hearing aids fitting.
    @Article{mariea2008,
      author   = {Mariam, M. and Delb, W. and Corona-Strauss, F. I. and Bloching, M. and Strauss, D. J.},
      journal  = {BioMed Journal 2008},
      title    = {Extraction of Habituation Correlates in Single Sweep Sequences of Late Auditory Evoked Potentials using Time-Scale Coherence: Objective Detection of Uncomfortable Loudness Level},
      year     = {2008},
      pages    = {601-605},
      abstract = {The fitting of cochlear implants as well as hearing aids requires information on the hearing threshold as well as on the uncomfortable loudness level. Due to its very subjective nature, the estimation of the uncomfortable loudness level is particularly challenging and represents a clinically unsolved problem. Using a computational monitoring of the habituation processes in single sweeps recordings of late auditory evoked potentials (LAEP), we propose a method that might be able to objectively determine the uncomfortable loudness level in non-cooperative patients such as newborns. Here we presented preliminary results of an ongoing study. Single sweep recordings of LAEP were performed at 2 stimulation levels, 50dB and and lOOdB hearing level (HL) with an interstimulus interval (ISI) of Is. In a group of 10 voluntary adult subjects with normal hearing, our scheme based on the analysis of single sweeps recordings and the calculation of time-scale phase coherence, the 1.12% reduction of time-scale phase coherence index for 50dB HL and 0.30% for lOOdB HL were observed. Therefore, habituation of 50dB HL stimulus had successfully been detected and no significant difference in sweeps evolution for 100dB HL stimulus (Wilcoxon test, significance level p <0.05). It is concluded that the proposed method possibly allows for the reliable detection of habituation and differentiation of comfortable from uncomfortable loudness levels in cochlear implants and hearing aids fitting.},
      keywords = {Habituation,Late auditory evoked potential,Time-scale coherence,Uncomfortable loudness level},
    }
  • D. J. Strauss, W. Delb, R. D'Amelio, Y. F. Low, and P. Falkai, "Objective Quantification of the Tinnitus Decompensation by Synchronization Measures of Auditory Evoked Single Sweeps," IEEE Transactions on Neural Systems and Rehabilitation Engineering, pp. 74-81, 2008. doi:10.1109/tnsre.2007.911086
    [BibTeX] [Abstract]
    Large-scale neural correlates of the tinnitus decompensation might be used for an objective evaluation of therapies and neurofeedback based therapeutic approaches. In this study, we try to identify large-scale neural correlates of the tinnitus decompensation using wavelet phase stability criteria of single sweep sequences of late auditory evoked potentials as synchronization stability measure. The extracted measure provided an objective quantification of the tinnitus decompensation and allowed for a reliable discrimination between a group of compensated and decompensated tinnitus patients. We provide an interpretation for our results by a neural model of top-down projections based on the Jastreboff tinnitus model combined with the adaptive resonance theory which has not been applied to model tinnitus so far. Using this model, our stability measure of evoked potentials can be linked to the focus of attention on the tinnitus signal. It is concluded that the wavelet phase stability of late auditory evoked potential single sweeps might be used as objective tinnitus decompensation measure and can be interpreted in the framework of the Jastreboff tinnitus model and adaptive resonance theory.
    @Article{straea2008,
      author   = {Strauss, D. J. and Delb, W. and D'Amelio, R. and Low, Y. F. and Falkai, P.},
      journal  = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
      title    = {Objective Quantification of the Tinnitus Decompensation by Synchronization Measures of Auditory Evoked Single Sweeps},
      year     = {2008},
      pages    = {74-81},
      abstract = {Large-scale neural correlates of the tinnitus decompensation might be used for an objective evaluation of therapies and neurofeedback based therapeutic approaches. In this study, we try to identify large-scale neural correlates of the tinnitus decompensation using wavelet phase stability criteria of single sweep sequences of late auditory evoked potentials as synchronization stability measure. The extracted measure provided an objective quantification of the tinnitus decompensation and allowed for a reliable discrimination between a group of compensated and decompensated tinnitus patients. We provide an interpretation for our results by a neural model of top-down projections based on the Jastreboff tinnitus model combined with the adaptive resonance theory which has not been applied to model tinnitus so far. Using this model, our stability measure of evoked potentials can be linked to the focus of attention on the tinnitus signal. It is concluded that the wavelet phase stability of late auditory evoked potential single sweeps might be used as objective tinnitus decompensation measure and can be interpreted in the framework of the Jastreboff tinnitus model and adaptive resonance theory.},
      doi      = {10.1109/tnsre.2007.911086},
      keywords = {Adaptive resonance theory,Attention,Auditory evoked responses,Synchronization stability,Tinnitus,Top-down processes,Wavelets},
    }
  • C. Trenado, L. Haab, and D. J. Strauss, "Multiscale Modeling of Auditory Attention: Forward Modeling of Large-Scale Neural Correlates in Evoked Potentials," IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 17, pp. 46-52, 2008.
    [BibTeX]
    @Article{trenea2008,
      author  = {Trenado, C. and Haab, L. and Strauss, D. J.},
      journal = {IEEE Transactions on Neural Systems and Rehabilitation Engineering},
      title   = {Multiscale Modeling of Auditory Attention: Forward Modeling of Large-Scale Neural Correlates in Evoked Potentials},
      year    = {2008},
      pages   = {46-52},
      volume  = {17},
    }
  • M. Busse, Y. F. Low, F. I. Corona-Strauss, W. Delb, and D. J. Strauss, "Neurofeedback by Neural Correlates of Auditory Selective Attention as Possible Application for Tinnitus Therapies," in Conf Proc IEEE Eng Med Biol Soc, 2008, pp. 5136-5139. doi:10.1109/iembs.2008.4650370
    [BibTeX] [Abstract]
    More and more people are suffering from tinnitus. There are many treatments for tinnitus that have been claimed based on different causes. Unfortunately, until now none of the existing treatments has been found to be effective in general. Here, we would like to suggest a treatment to tinnitus based on neurofeedback using neural correlates of auditory selective evoked potentials (ASEPs). We have shown that the wavelet phase synchronization of auditory late responses (ALR) single sweeps allows for a direct online monitoring of phase locked auditory attention. The results show that after a simple training, subjects learned to control their attention to the auditory modality. To improve the ability in the attention control system is an objective of many tinnitus treatments, so that the perception of the patients towards the tinnitus noise can be reduced to a minimum. It is concluded that our proposed neurofeedback system by wavelet phase synchronization measure might be used in a clinical treatment of tinnitus patients and it is possible to extent to other therapeutic based control systems.
    @InProceedings{bussea2008,
      author    = {Busse, M. and Low, Y. F. and Corona-Strauss, F. I. and Delb, W. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Neurofeedback by Neural Correlates of Auditory Selective Attention as Possible Application for Tinnitus Therapies},
      year      = {2008},
      pages     = {5136-5139},
      volume    = {2008:1},
      abstract  = {More and more people are suffering from tinnitus. There are many treatments for tinnitus that have been claimed based on different causes. Unfortunately, until now none of the existing treatments has been found to be effective in general. Here, we would like to suggest a treatment to tinnitus based on neurofeedback using neural correlates of auditory selective evoked potentials (ASEPs). We have shown that the wavelet phase synchronization of auditory late responses (ALR) single sweeps allows for a direct online monitoring of phase locked auditory attention. The results show that after a simple training, subjects learned to control their attention to the auditory modality. To improve the ability in the attention control system is an objective of many tinnitus treatments, so that the perception of the patients towards the tinnitus noise can be reduced to a minimum. It is concluded that our proposed neurofeedback system by wavelet phase synchronization measure might be used in a clinical treatment of tinnitus patients and it is possible to extent to other therapeutic based control systems.},
      doi       = {10.1109/iembs.2008.4650370},
    }
  • Y. F. Low, H. Argstatter, H. V. Bolay, and D. J. Strauss, "Evaluation of a Compact Tinnitus Therapy by Electrophysiological Tinnitus Decompensation Measures," in Conf Proc IEEE Eng Med Biol Soc, 2008, pp. 5132-5135. doi:10.1109/iembs.2008.4650369
    [BibTeX] [Abstract]
    Large-scale neural correlates of the tinnitus decompensation have been identified by using wavelet phase stability criteria of single sweep sequences of auditory late responses (ALRs). Our previous work showed that the synchronization stability in ALR sequences might be used for objective quantification of the tinnitus decompensation and attention which link to Jastreboff tinnitus model. In this study, we intend to provide an objective evaluation for quantifying the effect of music therapy in tinnitus patients. We examined neural correlates of the attentional mechanism in single sweep sequences of ALRs in chronic tinnitus patients who underwent compact therapy course by using the maximum entropy auditory paradigm. Results by our measure showed that the extent of differentiation between attended and unattended conditions improved significantly after the therapy. It is concluded that the wavelet phase synchronization stability of ALRs single sweeps can be used for the objective evaluation of tinnitus therapies, in this case the compact tinnitus music therapy.
    @InProceedings{lowea2008,
      author    = {Low, Y. F. and Argstatter, H. and Bolay, H. V. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Evaluation of a Compact Tinnitus Therapy by Electrophysiological Tinnitus Decompensation Measures},
      year      = {2008},
      pages     = {5132-5135},
      abstract  = {Large-scale neural correlates of the tinnitus decompensation have been identified by using wavelet phase stability criteria of single sweep sequences of auditory late responses (ALRs). Our previous work showed that the synchronization stability in ALR sequences might be used for objective quantification of the tinnitus decompensation and attention which link to Jastreboff tinnitus model. In this study, we intend to provide an objective evaluation for quantifying the effect of music therapy in tinnitus patients. We examined neural correlates of the attentional mechanism in single sweep sequences of ALRs in chronic tinnitus patients who underwent compact therapy course by using the maximum entropy auditory paradigm. Results by our measure showed that the extent of differentiation between attended and unattended conditions improved significantly after the therapy. It is concluded that the wavelet phase synchronization stability of ALRs single sweeps can be used for the objective evaluation of tinnitus therapies, in this case the compact tinnitus music therapy.},
      doi       = {10.1109/iembs.2008.4650369},
    }
  • I. Mustaffa, C. Trenado, K. Schwerdtfeger, and D. J. Strauss, "Evoked Response Denoising Using Nonlinear Diffusion Filtering of Single-Trial Matrix Representations," in Conf Proc IEEE Eng Med Biol Soc, 2008, pp. 3999-4002. doi:10.1109/iembs.2008.4650086
    [BibTeX]
    @InProceedings{mustea2008,
      author    = {Mustaffa, I. and Trenado, C. and Schwerdtfeger, K. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Evoked Response Denoising Using Nonlinear Diffusion Filtering of Single-Trial Matrix Representations},
      year      = {2008},
      pages     = {3999-4002},
      volume    = {2008:1},
      doi       = {10.1109/iembs.2008.4650086},
    }
  • D. J. Strauss, F. I. Corona-Strauss, and M. Froehlich, "Objective Estimation of the Listening Effort: Towards a Neuropsychological and Neurophysical Model," in Conf Proc IEEE Eng Med Biol Soc, 2008, pp. 1777-1780. doi:10.1109/iembs.2008.4649522
    [BibTeX] [Abstract]
    Modern hearing aid fitting could be revolutionized by the availability of objective methods for the listening effort estimation. However experimental and theoretical research dealing with this subject is still in its infancy. In this paper we present first results towards a neuropsychological and neurophyslcal model for the objective estimation of the listening effort by electroencephalographic, data. Our model Is based on intended endogenously driven top-down projections represented by corticothalamic feedback dynamics for auditory stream selection and their large-scale correlates in auditory evoked late responses. The predictions of the presented model are compared to experimental data obtained during different auditory tasks which required a graduated effort for their solutions. The experimental data verified the model predictions. It is concluded that the proposed neuropsychological and neurophysical modeling of stream selection provides an appropriate framework for listening effort estimation. The presented preliminary results of an ongoing study are encouraging, however, further focal research is necessary in order to estimate In how far the presented model and future extensions might support modern hearing aid fitting in practice.
    @InProceedings{straea2008c,
      author    = {Strauss, D. J. and Corona-Strauss, F. I. and Froehlich, M.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Objective Estimation of the Listening Effort: Towards a Neuropsychological and Neurophysical Model},
      year      = {2008},
      pages     = {1777-1780},
      volume    = {2008:1},
      abstract  = {Modern hearing aid fitting could be revolutionized by the availability of objective methods for the listening effort estimation. However experimental and theoretical research dealing with this subject is still in its infancy. In this paper we present first results towards a neuropsychological and neurophyslcal model for the objective estimation of the listening effort by electroencephalographic, data. Our model Is based on intended endogenously driven top-down projections represented by corticothalamic feedback dynamics for auditory stream selection and their large-scale correlates in auditory evoked late responses. The predictions of the presented model are compared to experimental data obtained during different auditory tasks which required a graduated effort for their solutions. The experimental data verified the model predictions. It is concluded that the proposed neuropsychological and neurophysical modeling of stream selection provides an appropriate framework for listening effort estimation. The presented preliminary results of an ongoing study are encouraging, however, further focal research is necessary in order to estimate In how far the presented model and future extensions might support modern hearing aid fitting in practice.},
      doi       = {10.1109/iembs.2008.4649522},
    }

2007

  • C. Trenado and D. J. Strauss, "Magnetic Nanoparticles for In Vivo Applications: A Numerical Modeling Study," Mathematical Modeling of Biological Systems, pp. 275-280, 2007. doi:10.1007/978-0-8176-4558-8_24
    [BibTeX] [Abstract]
    In vivo applications of biocompatible magnetic nanoparticles in a carrier liquid controlled by an external magnetic field from outside the body have recently been proposed for specific drug delivery such as in locoregional cancer therapies or the occlusion aneurysms. They can also be used as guided contrast agents in myocardial imaging after myocardial infarction. However, the choice of the optimal clinical setting still remains a challenge for all of the mentioned applications. A numerical heterogeneous multiscale model can be used for an optimal a priori determination of the free parameters and might help to overcome this problem.
    @Article{trenea2007,
      author    = {Trenado, C. and Strauss, D. J.},
      journal   = {Mathematical Modeling of Biological Systems},
      title     = {Magnetic Nanoparticles for In Vivo Applications: A Numerical Modeling Study},
      year      = {2007},
      pages     = {275-280},
      abstract  = {In vivo applications of biocompatible magnetic nanoparticles in a carrier liquid controlled by an external magnetic field from outside the body have recently been proposed for specific drug delivery such as in locoregional cancer therapies or the occlusion aneurysms. They can also be used as guided contrast agents in myocardial imaging after myocardial infarction. However, the choice of the optimal clinical setting still remains a challenge for all of the mentioned applications. A numerical heterogeneous multiscale model can be used for an optimal a priori determination of the free parameters and might help to overcome this problem.},
      booktitle = {Mathematical Modeling of Biological Systems},
      doi       = {10.1007/978-0-8176-4558-8_24},
      keywords  = {Biocompatible,Ferrofluids,Maxwell equations,Multiscale,Nanoparticles,Navier–stokes equations},
      publisher = {Birkhaeuser Boston},
    }
  • D. J. Strauss, W. Delb, and P. K. Plinkert, "Identification of Central Auditory Processing Disorders by Binaurally Evoked Brainstem Responses," Neural Engineering Handbook, pp. 59-80, 2007. doi:10.1002/9780470068298.ch4
    [BibTeX]
    @Article{straea2008b,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K.},
      journal   = {Neural Engineering Handbook},
      title     = {Identification of Central Auditory Processing Disorders by Binaurally Evoked Brainstem Responses},
      year      = {2007},
      pages     = {59-80},
      booktitle = {Handbook of Neural Engineering},
      doi       = {10.1002/9780470068298.ch4},
      keywords  = {Binaural evoked auditory brainstem responses (ABRs),CAPD identification by binaurally evoked brainstem responses,Central auditory processing disorder (CAPD) identification},
      publisher = {Wiley-IEEE Press},
    }
  • F. I. Corona-Strauss, W. Delb, M. Bloching, and D. J. Strauss, "Ultra-Fast Quantification of Hearing Loss by Neural Synchronization Stabilities of Auditory Evoked Brainstem Activity," in Conf Proc IEEE Eng Med Biol Soc, 2007, pp. 2476-2479. doi:10.1109/iembs.2007.4352830
    [BibTeX] [Abstract]
    Recently, we proposed a new novelty detection paradigm for the fast detection of hearing thresholds using single sweeps of auditory evoked potentials as efficient approach to newborn hearing screening. Such a method might prevent currently used time consuming averaging procedures which require the state of spontaneous sleep, sedation, or narcosis of the newborns when using such systems in universal newborn hearing screening programs. In this study, we present an evaluation of new feature for such novelty detection schemes, namely the synchronization stability of auditory evoked brainstem activity. For this, large-scale correlates of the neural group synchronization at the brainstem for stimulation levels above the hearing threshold are detected as novel event. This novelty detection paradigm allows for the adaptive inclusion of individual measurement conditions using the spontaneous EEG. For the individual patient, at the challenging stimulation level of 30dB(HL) the synchronization stability allowed the discrimination of stimulated from the non-stimulated condition in a fraction of time of conventional devices. It is concluded that the proposed feature following the novelty detection paradigm might be used for the ultra-fast detection of hearing thresholds and is thus ideally suited for the use in efficient universal hearing screening programs.
    @InProceedings{coroea2007,
      author    = {Corona-Strauss, F. I. and Delb, W. and Bloching, M. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Ultra-Fast Quantification of Hearing Loss by Neural Synchronization Stabilities of Auditory Evoked Brainstem Activity},
      year      = {2007},
      month     = {aug},
      pages     = {2476-2479},
      publisher = {{IEEE}},
      abstract  = {Recently, we proposed a new novelty detection paradigm for the fast detection of hearing thresholds using single sweeps of auditory evoked potentials as efficient approach to newborn hearing screening. Such a method might prevent currently used time consuming averaging procedures which require the state of spontaneous sleep, sedation, or narcosis of the newborns when using such systems in universal newborn hearing screening programs. In this study, we present an evaluation of new feature for such novelty detection schemes, namely the synchronization stability of auditory evoked brainstem activity. For this, large-scale correlates of the neural group synchronization at the brainstem for stimulation levels above the hearing threshold are detected as novel event. This novelty detection paradigm allows for the adaptive inclusion of individual measurement conditions using the spontaneous EEG. For the individual patient, at the challenging stimulation level of 30dB(HL) the synchronization stability allowed the discrimination of stimulated from the non-stimulated condition in a fraction of time of conventional devices. It is concluded that the proposed feature following the novelty detection paradigm might be used for the ultra-fast detection of hearing thresholds and is thus ideally suited for the use in efficient universal hearing screening programs.},
      doi       = {10.1109/iembs.2007.4352830},
    }
  • F. I. Corona-Strauss, W. Delb, M. Bloching, S. Hussain, and D. J. Strauss, "The Johor Screening Scheme: Is an Area-Wide Newborn Hearing Screening Possible in Malaysia?," in Conference Proceedings: 3rd International Conference of the IIHMSP, 2007, pp. 213-216. doi:10.1109/iih-msp.2007.296
    [BibTeX] [Abstract]
    Recently, we proposed a new novelty detection paradigm for the fast detection of hearing thresholds using single sweeps of auditory evoked potentials as efficient approach to newborn hearing screening. Such a method might prevent currently used time consuming averaging procedures which require the state of spontaneous sleep, sedation, or narcosis of the newborns when using such systems in universal newborn hearing screening programs. In this study, we present an evaluation of new feature for such novelty detection schemes, namely the synchronization stability of auditory evoked brainstem activity. It is concluded that the proposed feature following the novelty detection paradigm might be used for the ultra-fast detection of hearing thresholds and is thus ideally suited for the use in universal hearing screening programs.
    @InProceedings{coroea2007b,
      author    = {Corona-Strauss, F. I. and Delb, W. and Bloching, M. and Hussain, S. and Strauss, D. J.},
      booktitle = {Conference Proceedings: 3rd International Conference of the IIHMSP},
      title     = {The Johor Screening Scheme: Is an Area-Wide Newborn Hearing Screening Possible in Malaysia?},
      year      = {2007},
      month     = {nov},
      pages     = {213-216},
      publisher = {{IEEE}},
      abstract  = {Recently, we proposed a new novelty detection paradigm for the fast detection of hearing thresholds using single sweeps of auditory evoked potentials as efficient approach to newborn hearing screening. Such a method might prevent currently used time consuming averaging procedures which require the state of spontaneous sleep, sedation, or narcosis of the newborns when using such systems in universal newborn hearing screening programs. In this study, we present an evaluation of new feature for such novelty detection schemes, namely the synchronization stability of auditory evoked brainstem activity. It is concluded that the proposed feature following the novelty detection paradigm might be used for the ultra-fast detection of hearing thresholds and is thus ideally suited for the use in universal hearing screening programs.},
      doi       = {10.1109/iih-msp.2007.296},
    }
  • F. I. Corona-Strauss, D. J. Hecker, W. Delb, and D. J. Strauss, "Ultra-Fast Detection of Hearing Thresholds by Single Sweeps of Auditory Brainstem Responses: A New Novelty Detection Paradigm," in Neural Engineering, 2007. CNE 07. 3nd International IEEE/EMBS Conference on, 2007, pp. 638-641. doi:10.1109/cne.2007.369754
    [BibTeX] [Abstract]
    The evaluation of auditory brainstem responses (ABRs) is accepted to be the most reliable method for the objective diagnosis and quantification of hearing loss in newborns. However, in currently available setups and devices, a large number of sweeps has to be averaged to obtain a meaningful signal at low stimulation levels due to a poor signal-to-noise ratio. Due to the time consuming averaging procedure which requires the state of spontaneous sleep, sedation, or narcosis of the newborns, the evaluation of ABRs can only be used at the last stage of area-wide universal newborn hearing screening programs, increasing their implementation cost significantly and thus making their realization impossible in many cases. Here we propose a new novelty detection paradigm for the fast detection of hearing thresholds using the synchronization stability of auditory brainstem response single sweeps. For this, large-scale correlates of the neural group synchronization at the brainstem level by a stimulation level above the hearing threshold are detected as novel event. This novelty detection paradigm allows for the adaptive inclusion of individual measurement conditions using the spontaneous EEG. For the individual patient, at the challenging stimulation level of 30dB(HL) the synchronization stability allowed the discrimination of stimulated from the non-stimulated condition in a fraction of time of conventional devices used for newborn hearing screening. It is concluded that the proposed method might be used for the ultra-fast detection of hearing thresholds and is thus ideally suited for universal hearing screening programs.
    @InProceedings{coroea2007c,
      author    = {Corona-Strauss, F. I. and Hecker, D. J. and Delb, W. and Strauss, D. J.},
      booktitle = {Neural Engineering, 2007. CNE 07. 3nd International IEEE/EMBS Conference on},
      title     = {Ultra-Fast Detection of Hearing Thresholds by Single Sweeps of Auditory Brainstem Responses: A New Novelty Detection Paradigm},
      year      = {2007},
      pages     = {638-641},
      abstract  = {The evaluation of auditory brainstem responses (ABRs) is accepted to be the most reliable method for the objective diagnosis and quantification of hearing loss in newborns. However, in currently available setups and devices, a large number of sweeps has to be averaged to obtain a meaningful signal at low stimulation levels due to a poor signal-to-noise ratio. Due to the time consuming averaging procedure which requires the state of spontaneous sleep, sedation, or narcosis of the newborns, the evaluation of ABRs can only be used at the last stage of area-wide universal newborn hearing screening programs, increasing their implementation cost significantly and thus making their realization impossible in many cases. Here we propose a new novelty detection paradigm for the fast detection of hearing thresholds using the synchronization stability of auditory brainstem response single sweeps. For this, large-scale correlates of the neural group synchronization at the brainstem level by a stimulation level above the hearing threshold are detected as novel event. This novelty detection paradigm allows for the adaptive inclusion of individual measurement conditions using the spontaneous EEG. For the individual patient, at the challenging stimulation level of 30dB(HL) the synchronization stability allowed the discrimination of stimulated from the non-stimulated condition in a fraction of time of conventional devices used for newborn hearing screening. It is concluded that the proposed method might be used for the ultra-fast detection of hearing thresholds and is thus ideally suited for universal hearing screening programs.},
      doi       = {10.1109/cne.2007.369754},
    }
  • A. R. Harris and D. J. Strauss, "Adaptive Frame Decomposition in Slow Wave Cortical Responses to Transcranial Magnetic Stimulation," in Third International Conference on Intelligent Information Hiding and Multimedia Signal Processing, 2007, pp. 201-204. doi:10.1109/iih-msp.2007.70
    [BibTeX] [Abstract]
    Since the last two decades, the application of transcranial magnetic stimulation (TMS) is getting more interest for basic neurophysiological research and possibly diagnostic purposes. Nevertheless, the separation of magnetically from non-magnetically induced brain activity still remains a challenge due to superimposed secondary effects, in particular an auditory evoked potentials. An optimized tight wavelet frames is proposed for the adaptive extraction of discriminant electroencephalographic time-scale features during TMS and an auditory stimulation (AS) paradigm. This study is focused on large-scale features which correspond to slow wave cortical potentials (SCPs). These potentials might reflect thalamocortical dynamics and are frequently used in biofeedback therapies. The proposed methods allows for a robust extraction of slow wave components and separated clearly the TMS from the AS data. It is concluded that this study strongly supports recent suggestions that TMS modulates SCPs, reinforcing the theory that TMS leads to long term changes in the cortical excitability.
    @InProceedings{harrea2007,
      author    = {Harris, A. R. and Strauss, D. J.},
      booktitle = {Third International Conference on Intelligent Information Hiding and Multimedia Signal Processing},
      title     = {Adaptive Frame Decomposition in Slow Wave Cortical Responses to Transcranial Magnetic Stimulation},
      year      = {2007},
      month     = {nov},
      pages     = {201-204},
      publisher = {{IEEE}},
      volume    = {2},
      abstract  = {Since the last two decades, the application of transcranial magnetic stimulation (TMS) is getting more interest for basic neurophysiological research and possibly diagnostic purposes. Nevertheless, the separation of magnetically from non-magnetically induced brain activity still remains a challenge due to superimposed secondary effects, in particular an auditory evoked potentials. An optimized tight wavelet frames is proposed for the adaptive extraction of discriminant electroencephalographic time-scale features during TMS and an auditory stimulation (AS) paradigm. This study is focused on large-scale features which correspond to slow wave cortical potentials (SCPs). These potentials might reflect thalamocortical dynamics and are frequently used in biofeedback therapies. The proposed methods allows for a robust extraction of slow wave components and separated clearly the TMS from the AS data. It is concluded that this study strongly supports recent suggestions that TMS modulates SCPs, reinforcing the theory that TMS leads to long term changes in the cortical excitability.},
      doi       = {10.1109/iih-msp.2007.70},
    }
  • A. R. Harris, K. Schwerdtfeger, M. -A. Luszpinski, G. Sandvoss, and D. J. Strauss, "Adaptive Time-Scale Feature Extraction in Electroencephalographic Responses To Transcranial Magnetic Stimulation," in Conf Proc IEEE Eng Med Biol Soc, 2007, pp. 2835-2838. doi:10.1109/iembs.2007.4352919
    [BibTeX] [Abstract]
    Electroencephalograpic responses evoked by transcranial magnetic stimulation (TMS) gain more and more interest for basic neurophysiological research and possibly diagnostic purposes. However, the separation of magnetically from non-magnetically induced brain activity still remains a challenge due to superimposed secondary effects, in particular auditory and somatosensory evoked potentials. In this study, we use optimized tight wavelet frames for the adaptive extraction of discriminant electroencephalographic time-scale features during TMS using figure-of-eight coil for focal stimulation and a combined auditory and somatosensory stimulation (ASS) paradigm. We restrict our focus to large-scale features which correspond to slow wave cortical potentials (SCPs). These potentials might reflect thalamocortical dynamics and are frequently used in biofeedback therapies. The proposed methods allows for a robust extraction of slow wave components and separated clearly the TMS from the ASS data. It is concluded that our study strongly supports recent suggestions that TMS modulates SCPs, reinforcing the theory that TMS leads to long term changes in the cortical excitability.
    @InProceedings{harrea2007b,
      author    = {Harris, A. R. and Schwerdtfeger, K. and Luszpinski, M.-A. and Sandvoss, G. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Adaptive Time-Scale Feature Extraction in Electroencephalographic Responses To Transcranial Magnetic Stimulation},
      year      = {2007},
      pages     = {2835-2838},
      abstract  = {Electroencephalograpic responses evoked by transcranial magnetic stimulation (TMS) gain more and more interest for basic neurophysiological research and possibly diagnostic purposes. However, the separation of magnetically from non-magnetically induced brain activity still remains a challenge due to superimposed secondary effects, in particular auditory and somatosensory evoked potentials. In this study, we use optimized tight wavelet frames for the adaptive extraction of discriminant electroencephalographic time-scale features during TMS using figure-of-eight coil for focal stimulation and a combined auditory and somatosensory stimulation (ASS) paradigm. We restrict our focus to large-scale features which correspond to slow wave cortical potentials (SCPs). These potentials might reflect thalamocortical dynamics and are frequently used in biofeedback therapies. The proposed methods allows for a robust extraction of slow wave components and separated clearly the TMS from the ASS data. It is concluded that our study strongly supports recent suggestions that TMS modulates SCPs, reinforcing the theory that TMS leads to long term changes in the cortical excitability.},
      doi       = {10.1109/iembs.2007.4352919},
    }
  • Y. F. Low, F. I. Corona-Strauss, P. Adam, and D. J. Strauss, "Extraction of Auditory Attention Correlates in Single Sweeps of Cortical Potentials by Maximum Entropy Paradigms and its Application," in Neural Engineering, 2007. CNE 07. 3nd International IEEE/EMBS Conference on, 2007, pp. 469-472. doi:10.1109/cne.2007.369711
    [BibTeX] [Abstract]
    Recently, we have shown that the wavelet phase synchronization stability of single sweeps of auditory late responses (ALRs) allows for the quantification of the tinnitus decompensation. Our underlying model of adaptive resonance and spotlighting of attention links the synchronization stability directly to neural correlates of attention reflected in ALRs. Correlates of this attentional mechanism are further investigated in this study by using an auditory paradigm based on maximum entropy principle in healthy subjects. In particular, we show that the wavelet phase synchronization of ALR single sweeps allows for a direct online monitoring of phase locked auditory attention. Such an online monitoring cannot be implemented by known procedures as they are based on large-scale averages of ALRs. Apart from the objective quantification of the tinnitus decompensation, this measure can be used in every online and real time neurofeedback therapeutic approach where a direct stimulus locked attention monitoring is mandatory.
    @InProceedings{lowea2007,
      author    = {Low, Y. F. and Corona-Strauss, F. I. and Adam, P. and Strauss, D. J.},
      booktitle = {Neural Engineering, 2007. CNE 07. 3nd International IEEE/EMBS Conference on},
      title     = {Extraction of Auditory Attention Correlates in Single Sweeps of Cortical Potentials by Maximum Entropy Paradigms and its Application},
      year      = {2007},
      pages     = {469-472},
      abstract  = {Recently, we have shown that the wavelet phase synchronization stability of single sweeps of auditory late responses (ALRs) allows for the quantification of the tinnitus decompensation. Our underlying model of adaptive resonance and spotlighting of attention links the synchronization stability directly to neural correlates of attention reflected in ALRs. Correlates of this attentional mechanism are further investigated in this study by using an auditory paradigm based on maximum entropy principle in healthy subjects. In particular, we show that the wavelet phase synchronization of ALR single sweeps allows for a direct online monitoring of phase locked auditory attention. Such an online monitoring cannot be implemented by known procedures as they are based on large-scale averages of ALRs. Apart from the objective quantification of the tinnitus decompensation, this measure can be used in every online and real time neurofeedback therapeutic approach where a direct stimulus locked attention monitoring is mandatory.},
      doi       = {10.1109/cne.2007.369711},
    }
  • Y. F. Low, C. Trenado, W. Delb, F. I. Corona-Strauss, and D. J. Strauss, "The Role of Attention in the Tinnitus Decompensation: Reinforcement of a Large-Scale Neural Decompensation Measure," in Conf Proc IEEE Eng Med Biol Soc, 2007, pp. 2485-2488. doi:10.1109/iembs.2007.4352832
    [BibTeX] [Abstract]
    Large-scale neural correlates of the tinnitus decompensation have been identified by using wavelet phase stability criteria of single sweep sequences of auditory late responses (ALRs). The suggested measure provided an objective quantification of the tinnitus decompensation and allowed for a reliable discrimination between a group of compensated and decompensated tinnitus patients. By interpreting our results with an oscillatory tinnitus model, our synchronization stability measure of ALRs can be linked to the focus of attention on the tinnitus signal. In the following study, we examined in detail the correlates of this attentional mechanism in healthy subjects. The results support our previous findings of the phase synchronization stability measure that reflected neural correlates of the fixation of attention to the tinnitus signal. In this case, enabling the differentiation between the attended and unattended conditions. It is concluded that the wavelet phase synchronization stability of ALRs single sweeps can be used as objective tinnitus decompensation measure and can be interpreted in the framework of the Jastreboff tinnitus model and adaptive resonance theory. Our studies confirm that the synchronization stability in ALR sequences is linked to attention. This measure is not only able to serve as objective quantification of the tinnitus decompensation, but also can be applied in all online and real time neurofeedback therapeutic approach where a direct stimulus locked attention monitoring is compulsory as if it based on a single sweeps processing.
    @InProceedings{lowea2007b,
      author    = {Low, Y. F. and Trenado, C. and Delb, W. and Corona-Strauss, F. I. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {The Role of Attention in the Tinnitus Decompensation: Reinforcement of a Large-Scale Neural Decompensation Measure},
      year      = {2007},
      pages     = {2485-2488},
      abstract  = {Large-scale neural correlates of the tinnitus decompensation have been identified by using wavelet phase stability criteria of single sweep sequences of auditory late responses (ALRs). The suggested measure provided an objective quantification of the tinnitus decompensation and allowed for a reliable discrimination between a group of compensated and decompensated tinnitus patients. By interpreting our results with an oscillatory tinnitus model, our synchronization stability measure of ALRs can be linked to the focus of attention on the tinnitus signal. In the following study, we examined in detail the correlates of this attentional mechanism in healthy subjects. The results support our previous findings of the phase synchronization stability measure that reflected neural correlates of the fixation of attention to the tinnitus signal. In this case, enabling the differentiation between the attended and unattended conditions. It is concluded that the wavelet phase synchronization stability of ALRs single sweeps can be used as objective tinnitus decompensation measure and can be interpreted in the framework of the Jastreboff tinnitus model and adaptive resonance theory. Our studies confirm that the synchronization stability in ALR sequences is linked to attention. This measure is not only able to serve as objective quantification of the tinnitus decompensation, but also can be applied in all online and real time neurofeedback therapeutic approach where a direct stimulus locked attention monitoring is compulsory as if it based on a single sweeps processing.},
      doi       = {10.1109/iembs.2007.4352832},
    }
  • C. Trenado, L. Haab, and D. J. Strauss, "Modeling Neural Correlates of Auditory Attention in Evoked Potentials using Corticothalamic Feedback Dynamics," in Conf Proc IEEE Eng Med Biol Soc, 2007, pp. 4281-4284. doi:10.1109/iembs.2007.4353282
    [BibTeX] [Abstract]
    Auditory evoked cortical potentials (AECP) are well established as diagnostic tool in audiology and gain more and more impact in experimental neuropsychology, neuroscience, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation. The modulation of AECP due to exogenous and endogenous attention plays a major role in many clinical applications and has experimentally been studied in neuropsychology. However the relation of corticothalamic feedback dynamics to focal and non-focal attention and its large-scale effect reflected in AECPs is far from being understood. In this paper, we model neural correlates of auditory attention reflected in AECPs using corticothalamic feedback dynamics. We present a mapping of a recently developed multiscale model of evoked potentials to the hearing path and discuss for the first time its neurofunctionality in terms of corticothalamic feedback loops related to focal and non-focal attention. Our model reinforced recent experimental results related to online attention monitoring using AECPs with application as objective tinnitus decompensation measure. It is concluded that our model presents a promising approach to gain a deeper understanding of the neurodynamics of auditory attention and might be use as an efficient forward model to reinforce hypotheses that are obtained from experimental paradigms involving AECPs.
    @InProceedings{trenea2007b,
      author    = {Trenado, C. and Haab, L. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Modeling Neural Correlates of Auditory Attention in Evoked Potentials using Corticothalamic Feedback Dynamics},
      year      = {2007},
      pages     = {4281-4284},
      abstract  = {Auditory evoked cortical potentials (AECP) are well established as diagnostic tool in audiology and gain more and more impact in experimental neuropsychology, neuroscience, and psychiatry, e.g., for the attention deficit disorder, schizophrenia, or for studying the tinnitus decompensation. The modulation of AECP due to exogenous and endogenous attention plays a major role in many clinical applications and has experimentally been studied in neuropsychology. However the relation of corticothalamic feedback dynamics to focal and non-focal attention and its large-scale effect reflected in AECPs is far from being understood. In this paper, we model neural correlates of auditory attention reflected in AECPs using corticothalamic feedback dynamics. We present a mapping of a recently developed multiscale model of evoked potentials to the hearing path and discuss for the first time its neurofunctionality in terms of corticothalamic feedback loops related to focal and non-focal attention. Our model reinforced recent experimental results related to online attention monitoring using AECPs with application as objective tinnitus decompensation measure. It is concluded that our model presents a promising approach to gain a deeper understanding of the neurodynamics of auditory attention and might be use as an efficient forward model to reinforce hypotheses that are obtained from experimental paradigms involving AECPs.},
      doi       = {10.1109/iembs.2007.4353282},
    }
  • C. Trenado and D. J. Strauss, "Multiscale Multiphysics Modeling," in Proceeding of Invention 2007, 2007.
    [BibTeX]
    @inproceedings{trenea2007c,
      author = {Trenado, C. and Strauss, D. J.},
      title = {Multiscale Multiphysics Modeling},
      booktitle = {Proceeding of Invention 2007},
      year = {2007}
    }

2006

  • D. J. Hecker, W. Delb, F. I. Corona, and D. J. Strauss, "Possible Macroscopic Indicators of Neural Maturation in Subcortical Auditory Pathways in School-Age Children," in Conf Proc IEEE Eng Med Biol Soc, 2006, pp. 1173-1176. doi:10.1109/iembs.2006.259438
    [BibTeX] [Abstract]
    The examination of subcortical auditory processing by macroscopic electrophysiological measurements gains more and more interest in the group of school-age children, especially, in the objective diagnosis of the central auditory processing disorder. At the same time, recent behavioural and animal studies provided indicators for subcortical plasticity and neural maturation in auditory pathways in this age group. Therefore, it is important to examine which impact a possible neural maturation on subcortical large-scale electrophysiological diagnostic procedures has in this particular age. In this study, we compare auditory evoked brainstem responses of young adults and school-age children by a shift-invariant time-scale entropy as large-scale correlate of the neural group synchronization to an auditory stimulus. We found significant differences between these groups for binaurally evoked potentials under the condition of binaural fusion. It is therefore concluded that known difficulties in the evaluation of binaural interaction in children may stem from a neural maturation and increased plasticity.
    @InProceedings{heckea2006,
      author    = {Hecker, D. J. and Delb, W. and Corona, F. I. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Possible Macroscopic Indicators of Neural Maturation in Subcortical Auditory Pathways in School-Age Children},
      year      = {2006},
      pages     = {1173-1176},
      abstract  = {The examination of subcortical auditory processing by macroscopic electrophysiological measurements gains more and more interest in the group of school-age children, especially, in the objective diagnosis of the central auditory processing disorder. At the same time, recent behavioural and animal studies provided indicators for subcortical plasticity and neural maturation in auditory pathways in this age group. Therefore, it is important to examine which impact a possible neural maturation on subcortical large-scale electrophysiological diagnostic procedures has in this particular age. In this study, we compare auditory evoked brainstem responses of young adults and school-age children by a shift-invariant time-scale entropy as large-scale correlate of the neural group synchronization to an auditory stimulus. We found significant differences between these groups for binaurally evoked potentials under the condition of binaural fusion. It is therefore concluded that known difficulties in the evaluation of binaural interaction in children may stem from a neural maturation and increased plasticity.},
      doi       = {10.1109/iembs.2006.259438},
    }
  • Y. F. Low, C. Trenado, W. Delb, R. D'Amelio, and D. J. Strauss, "Large-Scale Inverse and Forward Modeling of Adaptive Resonance in the Tinnitus Decompensation," in Conf Proc IEEE Eng Med Biol Soc, 2006, pp. 2585-2588. doi:10.1109/iembs.2006.259445
    [BibTeX] [Abstract]
    Neural correlates of psychophysiological tinnitus models in humans may be used for their neurophysiological validation as well as for their refinement and improvement to better understand the pathogenesis of the tinnitus decompensation and to develop new therapeutic approaches. In this paper we make use of neural correlates of top-down projections, particularly, a recently introduced synchronization stability measure, together with a multiscale evoked response potential (ERP) model in order to study and evaluate the tinnitus decompensation by using a hybrid inverse-forward mathematical methodology. The neural synchronization stability, which according to the underlying model is linked to the focus of attention on the tinnitus signal, follows the experimental and inverse way and allows to discriminate between a group of compensated and decompensated tinnitus patients. The multiscale ERP model, which works in the forward direction, is used to consolidate hypotheses which are derived from the experiments for a known neural source dynamics related to attention. It is concluded that both methodologies agree and support each other in the description of the discriminatory character of the neural correlate proposed, but also help to fill the gap between the top-down adaptive resonance theory and the Jastreboff model of tinnitus.
    @InProceedings{lowea2006,
      author    = {Low, Y. F. and Trenado, C. and Delb, W. and D'Amelio, R. and Strauss, D. J.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Large-Scale Inverse and Forward Modeling of Adaptive Resonance in the Tinnitus Decompensation},
      year      = {2006},
      pages     = {2585-2588},
      abstract  = {Neural correlates of psychophysiological tinnitus models in humans may be used for their neurophysiological validation as well as for their refinement and improvement to better understand the pathogenesis of the tinnitus decompensation and to develop new therapeutic approaches. In this paper we make use of neural correlates of top-down projections, particularly, a recently introduced synchronization stability measure, together with a multiscale evoked response potential (ERP) model in order to study and evaluate the tinnitus decompensation by using a hybrid inverse-forward mathematical methodology. The neural synchronization stability, which according to the underlying model is linked to the focus of attention on the tinnitus signal, follows the experimental and inverse way and allows to discriminate between a group of compensated and decompensated tinnitus patients. The multiscale ERP model, which works in the forward direction, is used to consolidate hypotheses which are derived from the experiments for a known neural source dynamics related to attention. It is concluded that both methodologies agree and support each other in the description of the discriminatory character of the neural correlate proposed, but also help to fill the gap between the top-down adaptive resonance theory and the Jastreboff model of tinnitus.},
      doi       = {10.1109/iembs.2006.259445},
    }

2005

  • H. Schmidt, M. Akarsu, T. S. Müller, K. Moh, G. Schäfer, D. J. Strauss, and M. Naumann, "The formation of gradients in wet deposited coatings with photocatalytically active nanoparticles," Research on Chemical Intermediates, vol. 31, pp. 535-553, 2005. doi:10.1163/1568567053956680
    [BibTeX] [Abstract]
    A total of 81 doped and undoped anatase nano-particles were synthesised by a precipitation/co-precipitation process followed by a hydrothermal treatment to obtain increased visible light photocatalytic activity. The screening process was performed utilising a high throughput analysis system based on the photometric monitoring of the photocatalytic degradation of organic dyes (Rhodamine B, Malachite Green, Acid Blue 29). Photocatalytically active coatings were prepared with selected catalysts with high and low rankings from the screening. Degradation experiments with stearic acid could confirm the varying grades of visible light activity as seen in the screening process.
    @Article{schmea2005,
      author   = {Schmidt, H. and Akarsu, M. and M\"{u}ller, Th. S. and Moh, K. and Sch\"{a}fer, G. and Strauss, D. J. and Naumann, M.},
      journal  = {Research on Chemical Intermediates},
      title    = {The formation of gradients in wet deposited coatings with photocatalytically active nanoparticles},
      year     = {2005},
      pages    = {535-553},
      volume   = {31},
      abstract = {A total of 81 doped and undoped anatase nano-particles were synthesised by a precipitation/co-precipitation process followed by a hydrothermal treatment to obtain increased visible light photocatalytic activity. The screening process was performed utilising a high throughput analysis system based on the photometric monitoring of the photocatalytic degradation of organic dyes (Rhodamine B, Malachite Green, Acid Blue 29). Photocatalytically active coatings were prepared with selected catalysts with high and low rankings from the screening. Degradation experiments with stearic acid could confirm the varying grades of visible light activity as seen in the screening process.},
      doi      = {10.1163/1568567053956680},
      keywords = {Anatase,Coating,Dye degradation,Nanoparticle,Photocatalysis},
    }
  • D. J. Strauss and W. Delb, "On the Optimal Extraction of Neural Correlates of Binaural Interaction for Bilateral Cochlear Implant Adjustments," in Conf Proc IEEE Eng Med Biol Soc, 2005, pp. 5635-5638. doi:10.1109/iembs.2005.1615764
    [BibTeX] [Abstract]
    Accessible neural correlates of binaural interaction might be useful for the objective adjustment of cochlear implants in a bilateral implantation. A possible candidate could be the $\beta$-wave of binaural interaction components in auditory brainstem responses which has been shown to be an objective measure of binaural interaction. However a reliable and automated detection of this component capable of clinical use still remains a challenge and, moreover, it is mainly applied as discrete decision measure which does not allow for a quantitative assessment of binaural interaction. In this correspondence, we suggest a continuous time-scale feature of binaurally evoked brainstem responses for the quantitative assessment of binaural interaction in bilateral cochlear implant users. The extraction of such a feature by morphological local discriminant bases has recently been introduced in the objective diagnosis of the central auditory processing disorder. We show that this feature could be optimal for the adjustment of cochlear implants in the sense that it is continuous and allows for a machine based analysis. It is concluded that morphological local discriminant bases allow for the extraction of a continuous time-scale correlate of binaural interaction which seems to be applicable to objective bilateral cochlear implant adjustments.
    @InProceedings{straea2005,
      author    = {Strauss, D. J. and Delb, W.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {On the Optimal Extraction of Neural Correlates of Binaural Interaction for Bilateral Cochlear Implant Adjustments},
      year      = {2005},
      pages     = {5635-5638},
      publisher = {{IEEE}},
      abstract  = {Accessible neural correlates of binaural interaction might be useful for the objective adjustment of cochlear implants in a bilateral implantation. A possible candidate could be the $\beta$-wave of binaural interaction components in auditory brainstem responses which has been shown to be an objective measure of binaural interaction. However a reliable and automated detection of this component capable of clinical use still remains a challenge and, moreover, it is mainly applied as discrete decision measure which does not allow for a quantitative assessment of binaural interaction. In this correspondence, we suggest a continuous time-scale feature of binaurally evoked brainstem responses for the quantitative assessment of binaural interaction in bilateral cochlear implant users. The extraction of such a feature by morphological local discriminant bases has recently been introduced in the objective diagnosis of the central auditory processing disorder. We show that this feature could be optimal for the adjustment of cochlear implants in the sense that it is continuous and allows for a machine based analysis. It is concluded that morphological local discriminant bases allow for the extraction of a continuous time-scale correlate of binaural interaction which seems to be applicable to objective bilateral cochlear implant adjustments.},
      doi       = {10.1109/iembs.2005.1615764},
      keywords  = {Adapted filter banks,Binaural interaction,Cochlear implants,Feature extraction,Objective adjustment,Wavelets},
    }
  • D. J. Strauss, W. Delb, R. D'Amelio, and P. Falkai, "Neural Synchronization Stability in the Tinnitus Decompensation," in Neural Engineering, 2005 2nd International IEEE EMBS Conference on, 2005, pp. 186-189. doi:10.1109/cne.2005.1419586
    [BibTeX] [Abstract]
    Neural correlates of psychophysiological tinnitus models in humans may be used for their neurophysiological validation as well as for their refinement and improvement to better understand the pathogenesis of the tinnitus decompensation and to develop new therapeutic approaches. In this study, we try to identify neural correlates of cortico-cortical top-down projections based on the Jastreboff tinnitus model combined with the adaptive resonance theory of Grossberg which has not been applied to the problem of tinnitus so far. In particular, the neural synchronization stability in single sweep sequences of late auditory evoked potentials is evaluated by the wavelet phase coherence in the time-scale domain. The synchronization stability, which is according to the underlying model linked to the focus of attention on the tinnitus signal, discriminated between a group of compensated and decompensated tinnitus patients. It is concluded that top-down processes according to the adaptive resonance theory basically represent the influences of the limbic and autonomic nervous system in the Jastreboff tinnitus model. The neural correlates of these processes are globally reflected in the synchronization stability of late auditory evoked potentials and may be useful as objective tinnitus decompensation measure.
    @InProceedings{straea2005b,
      author    = {Strauss, D. J. and Delb, W. and D'Amelio, R. and Falkai, P.},
      booktitle = {Neural Engineering, 2005 2nd International IEEE EMBS Conference on},
      title     = {Neural Synchronization Stability in the Tinnitus Decompensation},
      year      = {2005},
      pages     = {186-189},
      publisher = {{IEEE}},
      abstract  = {Neural correlates of psychophysiological tinnitus models in humans may be used for their neurophysiological validation as well as for their refinement and improvement to better understand the pathogenesis of the tinnitus decompensation and to develop new therapeutic approaches. In this study, we try to identify neural correlates of cortico-cortical top-down projections based on the Jastreboff tinnitus model combined with the adaptive resonance theory of Grossberg which has not been applied to the problem of tinnitus so far. In particular, the neural synchronization stability in single sweep sequences of late auditory evoked potentials is evaluated by the wavelet phase coherence in the time-scale domain. The synchronization stability, which is according to the underlying model linked to the focus of attention on the tinnitus signal, discriminated between a group of compensated and decompensated tinnitus patients. It is concluded that top-down processes according to the adaptive resonance theory basically represent the influences of the limbic and autonomic nervous system in the Jastreboff tinnitus model. The neural correlates of these processes are globally reflected in the synchronization stability of late auditory evoked potentials and may be useful as objective tinnitus decompensation measure.},
      doi       = {10.1109/cne.2005.1419586},
      keywords  = {Adaptive resonance theory,Auditory evoked responses,Jastreboff model,Synchronization stability,Tinnitus,Top-down processes,Wavelets},
    }
  • D. J. Strauss and C. Trenado, "Modeling of Nanomaterials," in FEMLAB Conference, 2005, pp. 267-272.
    [BibTeX] [Download PDF]
    @InProceedings{straea2005c,
      author    = {Strauss, D. J. and Trenado, C.},
      booktitle = {FEMLAB Conference},
      title     = {Modeling of Nanomaterials},
      year      = {2005},
      pages     = {267-272},
      url       = {http://www.comsol.it/papers/1230/download/Strauss.pdf},
    }

2004

  • W. Delb, D. J. Strauss, and P. K. Plinkert, "Detection of binaural interaction in auditory brainstem responses using optimized wavelet packet decompositions.," International Journal of Audiology, vol. 43, pp. 69-78, 2004.
    [BibTeX]
    @Article{delbea2004,
      author  = {Delb, W. and Strauss, D. J. and Plinkert, P. K.},
      journal = {International Journal of Audiology},
      title   = {Detection of binaural interaction in auditory brainstem responses using optimized wavelet packet decompositions.},
      year    = {2004},
      pages   = {69-78},
      volume  = {43},
    }
  • W. Delb, D. J. Strauss, and P. K. Plinkert, "A time-frequency feature extraction scheme for the automated detection of binaural interaction in auditory brainstem responses," International Journal of Audiology, vol. 43, iss. 2, pp. 69-78, 2004. doi:10.1080/14992020400050012
    [BibTeX] [Abstract]
    The binaural interaction component (BIC), the difference between the summed monaurally evoked potentials of each ear and the binaurally evoked brainstem potentials, has been shown to be related to directional hearing. However, the detection of the $\beta$-peak as the most consistent part of the BIC is often difficult. Furthermore, there is no clearly defined signal feature characterizing the difference between the monaurally and the binaurally evoked brainstem responses. A closer look at the signals shows that amplitude differences as well as latency differences and variations in wave V slopes could be the reason for the formation of a $\beta$-peak. Using a time-scale feature extraction scheme, we were able to define a signal feature (morphological local discriminant bases (MLDB) coefficient 1) that accounts for the difference between the sum of the monaurally and binaurally evoked brainstem potentials. With use of this signal feature, reliable automated detection of differences between monaurally and binaurally evoked potentials is possible. As coefficient 1 replicates the behaviour of subjective measurements as well as of the BIC measurements, it can also be seen as a correlate of binaural interaction. With use of this signal feature, it is possible to judge from a given binaurally evoked potential whether it contains information on binaural interaction or not, without comparing it to the sum of the monaurally evoked brainstem responses. Consequently, binaural interaction can be assessed by one, instead of three, measurements by using the method described in this paper.
    @Article{delbea2004b,
      author    = {Delb, W. and Strauss, D. J. and Plinkert, P. K.},
      journal   = {International Journal of Audiology},
      title     = {A time-frequency feature extraction scheme for the automated detection of binaural interaction in auditory brainstem responses},
      year      = {2004},
      month     = {jan},
      number    = {2},
      pages     = {69-78},
      volume    = {43},
      abstract  = {The binaural interaction component (BIC), the difference between the summed monaurally evoked potentials of each ear and the binaurally evoked brainstem potentials, has been shown to be related to directional hearing. However, the detection of the $\beta$-peak as the most consistent part of the BIC is often difficult. Furthermore, there is no clearly defined signal feature characterizing the difference between the monaurally and the binaurally evoked brainstem responses. A closer look at the signals shows that amplitude differences as well as latency differences and variations in wave V slopes could be the reason for the formation of a $\beta$-peak. Using a time-scale feature extraction scheme, we were able to define a signal feature (morphological local discriminant bases (MLDB) coefficient 1) that accounts for the difference between the sum of the monaurally and binaurally evoked brainstem potentials. With use of this signal feature, reliable automated detection of differences between monaurally and binaurally evoked potentials is possible. As coefficient 1 replicates the behaviour of subjective measurements as well as of the BIC measurements, it can also be seen as a correlate of binaural interaction. With use of this signal feature, it is possible to judge from a given binaurally evoked potential whether it contains information on binaural interaction or not, without comparing it to the sum of the monaurally evoked brainstem responses. Consequently, binaural interaction can be assessed by one, instead of three, measurements by using the method described in this paper.},
      doi       = {10.1080/14992020400050012},
      keywords  = {Auditory brainstem responses,Central auditory processing disorders,Directional hearing,Feature extraction,Wavelet analysis},
      publisher = {Informa {UK} Limited},
    }
  • D. J. Strauss, G. Steidl, and U. Welzel, "Parameter detection of thin films from their X-ray reflectivity by support vector machines," Applied Numerical Mathematics, vol. 48, iss. 2, pp. 223-236, 2004. doi:10.1016/j.apnum.2003.07.002
    [BibTeX] [Abstract]
    Reflectivity measurements are used in thin film investigations for determining the density and the thickness of layered structures and the roughness of external and internal surfaces. From the mathematical point of view the deduction of these parameters from a measured reflectivity curve represents an inverse problem. At present, curve fitting procedures, based to a large extent on expert knowledge are commonly used in practice. These techniques are very time consuming and suffer from a low degree of automation. In this paper, we present a new method for the evaluation of reflectivity curves by the sparse approximation of multivariate vector-valued function mapping the reflectivity curves directly onto the thin film parameter set. This is the first method which solves the problem in a reasonable amount of time. Our approach utilizes an extended version of the optical matrix method as well as support vector machines for regression working in parallel. The solution of the corresponding quadratic programming problem makes use of the SVMTorch algorithm. We present numerical investigations to assess the performance of our method using models of practical relevance. It is concluded that the approximation by support vector machines represents a very promising tool in X-ray reflectivity investigations and seems also to be applicable for a much broader range of parameter detection problems in X-ray analysis.
    @Article{straea2004,
      author    = {Strauss, D. J. and Steidl, G. and Welzel, U.},
      journal   = {Applied Numerical Mathematics},
      title     = {Parameter detection of thin films from their X-ray reflectivity by support vector machines},
      year      = {2004},
      month     = {feb},
      number    = {2},
      pages     = {223-236},
      volume    = {48},
      abstract  = {Reflectivity measurements are used in thin film investigations for determining the density and the thickness of layered structures and the roughness of external and internal surfaces. From the mathematical point of view the deduction of these parameters from a measured reflectivity curve represents an inverse problem. At present, curve fitting procedures, based to a large extent on expert knowledge are commonly used in practice. These techniques are very time consuming and suffer from a low degree of automation. In this paper, we present a new method for the evaluation of reflectivity curves by the sparse approximation of multivariate vector-valued function mapping the reflectivity curves directly onto the thin film parameter set. This is the first method which solves the problem in a reasonable amount of time. Our approach utilizes an extended version of the optical matrix method as well as support vector machines for regression working in parallel. The solution of the corresponding quadratic programming problem makes use of the SVMTorch algorithm. We present numerical investigations to assess the performance of our method using models of practical relevance. It is concluded that the approximation by support vector machines represents a very promising tool in X-ray reflectivity investigations and seems also to be applicable for a much broader range of parameter detection problems in X-ray analysis.},
      doi       = {10.1016/j.apnum.2003.07.002},
      keywords  = {Optical matrix method,Radial basis functions,Reproducing kernel Hilbert spaces,Support vector machines,X-ray reflectometry},
      publisher = {Elsevier {BV}},
    }
  • D. J. Strauss, W. Delb, and P. K. Plinkert, "Objective Detection of the Central Auditory Processing Disorder: A New Machine Learning Approach," IEEE Transactions on Biomedical Engineering, vol. 51, iss. 7, pp. 1147-1155, 2004. doi:10.1109/tbme.2004.827948
    [BibTeX] [Abstract]
    The objective detection of binaural interaction is of diagnostic interest for the evaluation of the central auditory processing disorder (CAPD). The $\beta$-wave of the binaural interaction component in auditory brainstem responses has been suggested as an objective measure of binaural interaction and has been shown to be of diagnostic value in the CAPD diagnosis. However, a reliable and automated detection of the $\beta$-wave capable of clinical use still remains a challenge. We propose a new machine learning approach to the detection of the CAPD that is based on adapted tight frame decompositions which are tailored for support vector machines with radial kernels. Using shift-invariant scale and morphological features of the binaurally evoked brainstem potentials, our approach provides at least comparable results to the $\beta$-wave detection in view of the discrimination of subjects being at risk for CAPD and subjects being not at risk for CAPD. Furthermore, as no information from the monaurally potentials is necessary, the measurement cost is reduced by two-thirds compared to the computation of the binaural interaction component. We conclude that a machine learning approach in the form of a hybrid tight frame-support vector classification is effective in the objective detection of the CAPD.
    @Article{straea2004b,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K.},
      journal   = {{IEEE} Transactions on Biomedical Engineering},
      title     = {Objective Detection of the Central Auditory Processing Disorder: A New Machine Learning Approach},
      year      = {2004},
      month     = {jul},
      number    = {7},
      pages     = {1147-1155},
      volume    = {51},
      abstract  = {The objective detection of binaural interaction is of diagnostic interest for the evaluation of the central auditory processing disorder (CAPD). The $\beta$-wave of the binaural interaction component in auditory brainstem responses has been suggested as an objective measure of binaural interaction and has been shown to be of diagnostic value in the CAPD diagnosis. However, a reliable and automated detection of the $\beta$-wave capable of clinical use still remains a challenge. We propose a new machine learning approach to the detection of the CAPD that is based on adapted tight frame decompositions which are tailored for support vector machines with radial kernels. Using shift-invariant scale and morphological features of the binaurally evoked brainstem potentials, our approach provides at least comparable results to the $\beta$-wave detection in view of the discrimination of subjects being at risk for CAPD and subjects being not at risk for CAPD. Furthermore, as no information from the monaurally potentials is necessary, the measurement cost is reduced by two-thirds compared to the computation of the binaural interaction component. We conclude that a machine learning approach in the form of a hybrid tight frame-support vector classification is effective in the objective detection of the CAPD.},
      doi       = {10.1109/tbme.2004.827948},
      keywords  = {Auditory brainstem responses,Binaural interaction,Central auditory processing disorder (CAPD),Frames,Machine learning,Support vector machines,Wavelets},
      publisher = {Institute of Electrical and Electronics Engineers ({IEEE})},
    }
  • D. J. Strauss, W. Delb, and P. K. Plinkert, "A time–scale representation of binaural interaction components in auditory brainstem responses.," Computers in Biology and Medicine, vol. 34, pp. 461-477, 2004.
    [BibTeX]
    @Article{straea2004c,
      author  = {Strauss, D. J. and Delb, W. and Plinkert, P. K.},
      journal = {Computers in Biology and Medicine},
      title   = {A time–scale representation of binaural interaction components in auditory brainstem responses.},
      year    = {2004},
      pages   = {461-477},
      volume  = {34},
    }
  • D. J. Strauss, W. Delb, and P. K. Plinkert, "Analysis and Detection of Binaural Interaction in Auditory Brainstem Responses by Time-Scale Representations," Computers in Biology and Medicine, vol. 34, iss. 6, pp. 461-477, 2004. doi:10.1016/s0010-4825(03)00088-x
    [BibTeX] [Abstract]
    The $\beta$-wave of the binaural interaction component (BIC) in auditory evoked brainstem responses has been shown to be an objective measure of binaural interaction. However, a reliable and automated detection of this component capable of clinical use still remains a challenge. In this study, wavelet based time-scale representations of auditory evoked brainstem responses were investigated for the analysis of binaural interaction and for an automated detection of the $\beta$-wave. Twenty normal hearing subjects with verified normal directional hearing and speech intelligibility in noise were included in our study. In all of these subjects, the BICs exhibited a characteristic concentration of energy in the time-scale domain which allowed for an automated detection of the $\beta$-wave. Moreover, our study provides an explanation why the $\beta$-wave is hard to detect for larger interaural time delays using time-scale entropy based arguments. It is concluded that time-scale representations of auditory brainstem responses are well suited for the analysis of binaural interaction and allow for an automated detection of the $\beta$-wave.
    @Article{straea2004d,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K.},
      journal   = {Computers in Biology and Medicine},
      title     = {Analysis and Detection of Binaural Interaction in Auditory Brainstem Responses by Time-Scale Representations},
      year      = {2004},
      month     = {sep},
      number    = {6},
      pages     = {461-477},
      volume    = {34},
      abstract  = {The $\beta$-wave of the binaural interaction component (BIC) in auditory evoked brainstem responses has been shown to be an objective measure of binaural interaction. However, a reliable and automated detection of this component capable of clinical use still remains a challenge. In this study, wavelet based time-scale representations of auditory evoked brainstem responses were investigated for the analysis of binaural interaction and for an automated detection of the $\beta$-wave. Twenty normal hearing subjects with verified normal directional hearing and speech intelligibility in noise were included in our study. In all of these subjects, the BICs exhibited a characteristic concentration of energy in the time-scale domain which allowed for an automated detection of the $\beta$-wave. Moreover, our study provides an explanation why the $\beta$-wave is hard to detect for larger interaural time delays using time-scale entropy based arguments. It is concluded that time-scale representations of auditory brainstem responses are well suited for the analysis of binaural interaction and allow for an automated detection of the $\beta$-wave.},
      doi       = {10.1016/s0010-4825(03)00088-x},
      keywords  = {Auditory brainstem responses,Binaural interaction,EEG analysis,Entropy analysis,Time-scale representation,Wavelets},
      publisher = {Elsevier {BV}},
    }
  • D. J. Strauss, M. A. Pinsky, and H. Schmidt, "Simulation von magnetischen Nano-Träger-Systemen in der Tumortherapie," Physik-Journal, vol. 3, pp. 88-90, 2004.
    [BibTeX]
    @article{straea2004e,
      author = {Strauss, D. J. and Pinsky, M. A. and Schmidt, H.},
      title = {Simulation von magnetischen Nano-Tr\"{a}ger-Systemen in der Tumortherapie},
      journal = {Physik-Journal},
      volume = {3},
      pages = {88-90},
      year = {2004}
    }
  • W. Delb, D. J. Strauss, and P. K. Plinkert, "Binaural Interaction Components (BIC) - A possible diagnostic tool in pediatric cochlear implant implantation," in 7th European Symposium on Paediatric Cochlear Implantation, 2004.
    [BibTeX]
    @inproceedings{delbea2004d,
      author = {Delb, W. and Strauss, D. J. and Plinkert, P. K.},
      title = {Binaural Interaction Components (BIC) - A possible diagnostic tool in pediatric cochlear implant implantation},
      booktitle = {7th European Symposium on Paediatric Cochlear Implantation},
      year = {2004}
    }
  • D. J. Strauss, W. Delb, P. K. Plinkert, and H. Schmidt, "Fast Detection of Wave V in ABRs Using a Smart Single Sweep Analysis System," in Conf Proc IEEE Eng Med Biol Soc, 2004, pp. 458-461. doi:10.1109/iembs.2004.1403193
    [BibTeX] [Abstract]
    The analysis of auditory brainstem responses (ABRs) is accepted to be the most reliable method for the objective diagnosis and quantification of hearing loss in newborns. However, in currently available setups, a large number of sweeps has to be averaged to obtain a meaningful signal at low stimulation levels due to a poor signal-to-noise ratio. In this study, we present a new approach to the detection of wave V in ABRs using a smart single sweep analysis system. A small number of sweeps is decomposed by optimized tight frames and evaluated by a kernel based novelty detection machine. This hybrid supervised learning scheme is combined with an inter-sweep dissimilarity tracing for the final decision making. At the challenging stimulation level of 30 dB, our system reached a reasonable specificity and sensitivity for the detection of wave V in a fraction of the measurement time of conventional schemes.
    @InProceedings{straea2004f,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K. and Schmidt, H.},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Fast Detection of Wave V in ABRs Using a Smart Single Sweep Analysis System},
      year      = {2004},
      pages     = {458-461},
      publisher = {{IEEE}},
      abstract  = {The analysis of auditory brainstem responses (ABRs) is accepted to be the most reliable method for the objective diagnosis and quantification of hearing loss in newborns. However, in currently available setups, a large number of sweeps has to be averaged to obtain a meaningful signal at low stimulation levels due to a poor signal-to-noise ratio. In this study, we present a new approach to the detection of wave V in ABRs using a smart single sweep analysis system. A small number of sweeps is decomposed by optimized tight frames and evaluated by a kernel based novelty detection machine. This hybrid supervised learning scheme is combined with an inter-sweep dissimilarity tracing for the final decision making. At the challenging stimulation level of 30 dB, our system reached a reasonable specificity and sensitivity for the detection of wave V in a fraction of the measurement time of conventional schemes.},
      doi       = {10.1109/iembs.2004.1403193},
      keywords  = {Adapted Filter Banks,Auditory Brainstem Responses,Hearing Screening,Kernel Machines,Single Sweep Analysis,Smart Systems,Wavelets},
    }

2003

  • W. Delb, D. J. Strauss, G. Hohenberg, and P. K. Plinkert, "The Binaural Interaction Component in Children with Central Auditory Processing Disorders," International Journal of Audiology, vol. 42, iss. 7, pp. 401-412, 2003. doi:10.3109/14992020309080049
    [BibTeX] [Abstract]
    The detection of binaural interaction is of diagnostic interest in patients with central auditory processing disorders (CAPDs), as binaural hearing tasks are frequently affected in these patients. Owing to the comorbidity associated with disorders such as an attention-deficit hyperactivity disorder, pathological results in subjective tests often show extra-auditory factors such as reduced attention rather than impaired central auditory function. Therefore, objective measures for auditory processing disorders are essential. The binaural interaction component (BIC), which is the arithmetical difference between the sum of the monaurally evoked auditory potentials of each ear and the binaurally evoked brainstem potentials, has been used as an objective measure of binaural interaction in humans. BIC measurements can therefore be considered as a possible diagnostic tool in CAPD patients. One aim of the present study was to examine whether and to what extent BIC measurements are capable of differentiating between normal children and children 'at risk for CAPD'. BIC measurements were performed on 17 children at risk for CAPD and in a group of 25 children with normal results in the central audiometric tests used. Using the presence or absence of clearly demonstrable BIC waveforms as an indication of whether a CAPD is present or not, a sensitivity and specificity of 76% could be achieved. We conclude that BIC measurements might be of some diagnostic value in CAPD patients.
    @Article{delbea2003,
      author    = {Delb, W. and Strauss, D. J. and Hohenberg, G. and Plinkert, P. K.},
      journal   = {International Journal of Audiology},
      title     = {The Binaural Interaction Component in Children with Central Auditory Processing Disorders},
      year      = {2003},
      month     = {jan},
      number    = {7},
      pages     = {401-412},
      volume    = {42},
      abstract  = {The detection of binaural interaction is of diagnostic interest in patients with central auditory processing disorders (CAPDs), as binaural hearing tasks are frequently affected in these patients. Owing to the comorbidity associated with disorders such as an attention-deficit hyperactivity disorder, pathological results in subjective tests often show extra-auditory factors such as reduced attention rather than impaired central auditory function. Therefore, objective measures for auditory processing disorders are essential. The binaural interaction component (BIC), which is the arithmetical difference between the sum of the monaurally evoked auditory potentials of each ear and the binaurally evoked brainstem potentials, has been used as an objective measure of binaural interaction in humans. BIC measurements can therefore be considered as a possible diagnostic tool in CAPD patients. One aim of the present study was to examine whether and to what extent BIC measurements are capable of differentiating between normal children and children 'at risk for CAPD'. BIC measurements were performed on 17 children at risk for CAPD and in a group of 25 children with normal results in the central audiometric tests used. Using the presence or absence of clearly demonstrable BIC waveforms as an indication of whether a CAPD is present or not, a sensitivity and specificity of 76% could be achieved. We conclude that BIC measurements might be of some diagnostic value in CAPD patients.},
      doi       = {10.3109/14992020309080049},
      publisher = {Informa {UK} Limited},
    }
  • D. J. Strauss, G. Steidl, and W. Delb, "Feature extraction by shape-adapted local discriminant bases," Signal Processing, vol. 83, iss. 2, pp. 359-376, 2003. doi:10.1016/s0165-1684(02)00420-6
    [BibTeX] [Abstract]
    In recent years, wavelet packets have proven their capabilities for dimensionality reduction in waveform recognition. A well-accepted scheme is the local discriminant bases (LDB) algorithm which relies on the best-basis paradigm. In this paper, we combine the LDB algorithm with signal-adapted filter banks based on the lattice structure to construct more powerful LDBs. Here, additionally to the conventional tree adjustment, we adapt the shape of the analyzing atoms to extract discriminatory information among signal classes. We apply our shape-adapted LDBs, which we also call morphological LDBs, for current tasks of biosignal processing, namely feature extraction in waveforms from audiology and electrocardiology. Against the background of these applications, we show that our morphological LDBs outperform LDBs based on a fixed dictionary. We also present results which seem to open new research perspectives in audiology.
    @Article{straea2003,
      author    = {Strauss, D. J. and Steidl, G. and Delb, W.},
      journal   = {Signal Processing},
      title     = {Feature extraction by shape-adapted local discriminant bases},
      year      = {2003},
      month     = {feb},
      number    = {2},
      pages     = {359-376},
      volume    = {83},
      abstract  = {In recent years, wavelet packets have proven their capabilities for dimensionality reduction in waveform recognition. A well-accepted scheme is the local discriminant bases (LDB) algorithm which relies on the best-basis paradigm. In this paper, we combine the LDB algorithm with signal-adapted filter banks based on the lattice structure to construct more powerful LDBs. Here, additionally to the conventional tree adjustment, we adapt the shape of the analyzing atoms to extract discriminatory information among signal classes. We apply our shape-adapted LDBs, which we also call morphological LDBs, for current tasks of biosignal processing, namely feature extraction in waveforms from audiology and electrocardiology. Against the background of these applications, we show that our morphological LDBs outperform LDBs based on a fixed dictionary. We also present results which seem to open new research perspectives in audiology.},
      doi       = {10.1016/s0165-1684(02)00420-6},
      keywords  = {Biosignal processing,Dimensionality reduction,Local discriminant bases,Signal-adapted filter banks,Waveform recognition,Wavelet packets},
      publisher = {Elsevier {BV}},
    }
  • D. J. Strauss, W. Delb, P. K. Plinkert, and J. Jung, "Hybrid Wavelet-Kernel Based Classifiers and Novelty Detectors in Biosignal Processing," in Conf Proc IEEE Eng Med Biol Soc, 2003, pp. 2765-2769. doi:10.1109/iembs.2003.1280516
    [BibTeX] [Abstract]
    The recognition of waveforms represents a major challenge in biosignal processing. In this area, the recognition scheme has to offer a particular high generalization performance and should often allow for the inclusion prior knowledge about the waveforms. In this paper, we propose a hybrid machine learning scheme as general approach to waveform recognition in the biomedical area. Our hybrid scheme is based on feature extractions by adapted filter banks and support vector machines or kernel based novelty detectors. It allows for the inclusion of a priori knowledge such as local instabilities in time and shift-variance of bioelectric waveforms. We apply our scheme for the classification of endocardial waveforms and the detection of transient evoked otoacoustic emissions. For both applications, we show that our scheme outperforms conventional methods used before.
    @InProceedings{straea2003b,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K. and J. Jung},
      booktitle = {Conf Proc IEEE Eng Med Biol Soc},
      title     = {Hybrid Wavelet-Kernel Based Classifiers and Novelty Detectors in Biosignal Processing},
      year      = {2003},
      pages     = {2765-2769},
      publisher = {{IEEE}},
      abstract  = {The recognition of waveforms represents a major challenge in biosignal processing. In this area, the recognition scheme has to offer a particular high generalization performance and should often allow for the inclusion prior knowledge about the waveforms. In this paper, we propose a hybrid machine learning scheme as general approach to waveform recognition in the biomedical area. Our hybrid scheme is based on feature extractions by adapted filter banks and support vector machines or kernel based novelty detectors. It allows for the inclusion of a priori knowledge such as local instabilities in time and shift-variance of bioelectric waveforms. We apply our scheme for the classification of endocardial waveforms and the detection of transient evoked otoacoustic emissions. For both applications, we show that our scheme outperforms conventional methods used before.},
      doi       = {10.1109/iembs.2003.1280516},
      keywords  = {Adapted Filter Banks,Auditory Brainstem Responses,Endocardial Signals,Frames,Support Vector Machines,Wavelets},
    }
  • D. J. Strauss, W. Delb, P. K. Plinkert, and J. Jung, "Adapted filter banks in machine learning: Applications in biomedical signal processing," in Proceedings on the IEEE International Conference on Acoustic, Speech and Signal Processing, 2003, p. 425(VI)-428(VI). doi:10.1109/icassp.2003.1201709
    [BibTeX] [Abstract]
    The theory of signal-adapted filter banks has been developed in signal compression in recent years and only rarely be applied to other applications fields such as machine learning. In this paper, we propose lattice structure based signal-adapted filter banks and time-scale atoms, respectively, for the construction of morphological local discriminant bases and hybrid wavelet-support vector classifiers. The first mentioned method is a more powerful construction of the recently introduced local discriminant bases algorithm which employs, additionally to the conventional wavelet-packet tree adjustment, an adaptation of the analyzing time-scale atoms. The latter mentioned method utilizes adapted wavelet decompositions which are tailored for support vector classifiers with radial basis functions as kernels. For both methods, we present applications in biomedical signal processing.
    @InProceedings{straea2003c,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K. and Jung, J.},
      booktitle = {Proceedings on the IEEE International Conference on Acoustic, Speech and Signal Processing},
      title     = {Adapted filter banks in machine learning: Applications in biomedical signal processing},
      year      = {2003},
      pages     = {425(VI)-428(VI)},
      publisher = {{IEEE}},
      abstract  = {The theory of signal-adapted filter banks has been developed in signal compression in recent years and only rarely be applied to other applications fields such as machine learning. In this paper, we propose lattice structure based signal-adapted filter banks and time-scale atoms, respectively, for the construction of morphological local discriminant bases and hybrid wavelet-support vector classifiers. The first mentioned method is a more powerful construction of the recently introduced local discriminant bases algorithm which employs, additionally to the conventional wavelet-packet tree adjustment, an adaptation of the analyzing time-scale atoms. The latter mentioned method utilizes adapted wavelet decompositions which are tailored for support vector classifiers with radial basis functions as kernels. For both methods, we present applications in biomedical signal processing.},
      doi       = {10.1109/icassp.2003.1201709},
    }
  • D. J. Strauss, W. Delb, and P. K. Plinkert, "Identification of Central Auditory Processing Disorders by Scale and Entropy Features of Binaural Auditory Brainstem Potentials," in First International IEEE EMBS Conference on Neural Engineering, 2003. Conference Proceedings., 2003, pp. 410-413. doi:10.1109/cne.2003.1196848
    [BibTeX] [Abstract]
    The $\beta$-wave of the binaural interaction component in auditory brainstem responses has been suggested as an objective measure of binaural interaction and has been shown to be of diagnostic value in the diagnosis of the central auditory processing disorder (CAPD). However, a reliable and automated detection of the $\beta$-wave capable of clinical use still remains a challenge. In this correspondence, we introduce a new approach to the identification of the CAPD by scale and entropy features of binaural auditory brainstem potentials. For the feature extraction, we apply adapted tight-frame decompositions which are tailored for a subsequent classification by support vector machines. Our approach provides at least comparable results as the beta detection for the discrimination of patients being at risk for CAPD and patients not being at risk for CAPD but with the major advantage that it is truly objective. Furthermore, as no information from the monaurally evoked potentials is necessary, the measurement cost is reduced by two third compared to the computation of the binaural interaction component We conclude that a classification of scale and entropy features of binaural auditory brainstem potentials is very effective for the identification of central auditory processing disorders.
    @InProceedings{straea2003d,
      author    = {Strauss, D. J. and Delb, W. and Plinkert, P. K.},
      booktitle = {First International {IEEE} {EMBS} Conference on Neural Engineering, 2003. Conference Proceedings.},
      title     = {Identification of Central Auditory Processing Disorders by Scale and Entropy Features of Binaural Auditory Brainstem Potentials},
      year      = {2003},
      pages     = {410-413},
      publisher = {{IEEE}},
      abstract  = {The $\beta$-wave of the binaural interaction component in auditory brainstem responses has been suggested as an objective measure of binaural interaction and has been shown to be of diagnostic value in the diagnosis of the central auditory processing disorder (CAPD). However, a reliable and automated detection of the $\beta$-wave capable of clinical use still remains a challenge. In this correspondence, we introduce a new approach to the identification of the CAPD by scale and entropy features of binaural auditory brainstem potentials. For the feature extraction, we apply adapted tight-frame decompositions which are tailored for a subsequent classification by support vector machines. Our approach provides at least comparable results as the beta detection for the discrimination of patients being at risk for CAPD and patients not being at risk for CAPD but with the major advantage that it is truly objective. Furthermore, as no information from the monaurally evoked potentials is necessary, the measurement cost is reduced by two third compared to the computation of the binaural interaction component We conclude that a classification of scale and entropy features of binaural auditory brainstem potentials is very effective for the identification of central auditory processing disorders.},
      doi       = {10.1109/cne.2003.1196848},
      keywords  = {Artificial intelligence,Auditory system,Costs,Entropy,Feature extraction,Hospitals,Pattern recognition,Signal processing,Support vector machine classification,Support vector machines},
    }
  • D. J. Strauss and J. Jung, "Feasibility of Wavelet-Kernel Novelty Detectors for Identifying Ventricular Tachycardia," in IEEE CinC 30, 2003. doi:10.1109/cic.2003.1291209
    [BibTeX] [Abstract]
    Hybrid wavelet-support vector classifiers have recently been suggested as efficient rate independent recognition scheme for endocardial electrograms (EEs) usable in implantable cardioverter defibrillators (ICDs). However, these schemes involve waveforms of the normal sinus rhythm (NSR) as well as the pathological rhythm. In this study, we assess the feasibility of hybrid wavelet-kernel novelty detectors to discriminate between NSR and ventricular tachycardia (VT). These schemes only involve waveforms of NSR for the learning task. Consecutive beats were selected as morphological patterns of NSR and VT. These patters were represented by their multilevel concentrations using a lattice structure based wavelet decomposition. The lattice angles were optimized for kernel based novelty detectors. In a blind analysis of the independent test set, our scheme outperformed the correlation waveform analysis with best fit alignment which is a well accepted method for arrhythmia recognition. However, the performance of wavelet-support vector classifiers was not achievable. We conclude that wavelet-kernel novelty detectors are feasible for the rate independent identification of VTs. Our scheme is of a low complexity and suitable for efficient real-time implementations. However, further studies are needed to evaluate their performance in the clinical practice.
    @InProceedings{straea2003e,
      author    = {Strauss, D. J. and Jung, J.},
      booktitle = {IEEE CinC 30},
      title     = {Feasibility of Wavelet-Kernel Novelty Detectors for Identifying Ventricular Tachycardia},
      year      = {2003},
      editor    = {Murray, A. and Swiryn, S.},
      publisher = {{IEEE}},
      abstract  = {Hybrid wavelet-support vector classifiers have recently been suggested as efficient rate independent recognition scheme for endocardial electrograms (EEs) usable in implantable cardioverter defibrillators (ICDs). However, these schemes involve waveforms of the normal sinus rhythm (NSR) as well as the pathological rhythm. In this study, we assess the feasibility of hybrid wavelet-kernel novelty detectors to discriminate between NSR and ventricular tachycardia (VT). These schemes only involve waveforms of NSR for the learning task. Consecutive beats were selected as morphological patterns of NSR and VT. These patters were represented by their multilevel concentrations using a lattice structure based wavelet decomposition. The lattice angles were optimized for kernel based novelty detectors. In a blind analysis of the independent test set, our scheme outperformed the correlation waveform analysis with best fit alignment which is a well accepted method for arrhythmia recognition. However, the performance of wavelet-support vector classifiers was not achievable. We conclude that wavelet-kernel novelty detectors are feasible for the rate independent identification of VTs. Our scheme is of a low complexity and suitable for efficient real-time implementations. However, further studies are needed to evaluate their performance in the clinical practice.},
      doi       = {10.1109/cic.2003.1291209},
    }

2002

  • D. J. Strauss and G. Steidl, "Hybrid wavelet-support vector classifiers of waveforms," Journal of Computational and Applied Mathematics, vol. 148, pp. 375-400, 2002.
    [BibTeX]
    @Article{straea2002,
      author  = {Strauss, D. J. and Steidl, G.},
      journal = {Journal of Computational and Applied Mathematics},
      title   = {Hybrid wavelet-support vector classifiers of waveforms},
      year    = {2002},
      pages   = {375-400},
      volume  = {148},
    }
  • W. Delb, G. Hohenberg, D. J. Strauss, and P. K. Plinkert, "Binaurale Differenzpotentiale früher auditorisch evozierter Potentiale - Normalwertebestimmung und Einfluss einer interauralen Zeit- und Pegeldifferenz," Laryngo-Rhino-Otologie, vol. 81, iss. 8, pp. 551-557, 2002. doi:10.1055/s-2002-33364
    [BibTeX] [Abstract]
    Background: Binaural interaction components of auditory brainstem responses have long been studied and its $\beta$-wave has been shown to be correlated with directional hearing ability. As patients with auditory processing disorders such as patients with some sorts of learning disabilities frequently have difficulties with binaural processing it seems sensible to use binaural interaction components in the diagnosis of these disorders. Methods: In order to obtain normal values and to investigate the influence of interaural time (ITD) and level differences (ILD) binaural interaction components were measured in 21 adults. Interaural time differences varied between 0 and 1.2 ms and interaural level differences between 0 and 30 dB. Results: $\beta$-latencies increased significantly as interaural time differences increased while $\beta$-amplitudes did not change significantly. In measurements with higher interaural time differences detection of the $\beta$-wave was only rarely possible. The effect of interaural level differences on $\beta$-latencies was less pronounced and not significant as well as the influence of interaural level differences on $\beta$-amplitudes. Conclusions: In the present study it could be shown that the beta-wave of the binaural interaction waveform is present in almost every normal hearing subject. As amplitudes show a considerable variation beta-latencies seem to be of higher diagnostic value than amplitudes.
    @Article{delbea2002,
      author    = {Delb, W. and Hohenberg, G. and Strauss, D. J. and Plinkert, P. K.},
      journal   = {Laryngo-Rhino-Otologie},
      title     = {Binaurale Differenzpotentiale fr\"{u}her auditorisch evozierter Potentiale - Normalwertebestimmung und Einfluss einer interauralen Zeit- und Pegeldifferenz},
      year      = {2002},
      month     = {aug},
      number    = {8},
      pages     = {551-557},
      volume    = {81},
      abstract  = {Background: Binaural interaction components of auditory brainstem responses have long been studied and its $\beta$-wave has been shown to be correlated with directional hearing ability. As patients with auditory processing disorders such as patients with some sorts of learning disabilities frequently have difficulties with binaural processing it seems sensible to use binaural interaction components in the diagnosis of these disorders. Methods: In order to obtain normal values and to investigate the influence of interaural time (ITD) and level differences (ILD) binaural interaction components were measured in 21 adults. Interaural time differences varied between 0 and 1.2 ms and interaural level differences between 0 and 30 dB. Results: $\beta$-latencies increased significantly as interaural time differences increased while $\beta$-amplitudes did not change significantly. In measurements with higher interaural time differences detection of the $\beta$-wave was only rarely possible. The effect of interaural level differences on $\beta$-latencies was less pronounced and not significant as well as the influence of interaural level differences on $\beta$-amplitudes. Conclusions: In the present study it could be shown that the beta-wave of the binaural interaction waveform is present in almost every normal hearing subject. As amplitudes show a considerable variation beta-latencies seem to be of higher diagnostic value than amplitudes.},
      doi       = {10.1055/s-2002-33364},
      keywords  = {Binaural interaction,Binaural interaction component,ILD,ITD,Normative data},
      publisher = {Georg Thieme Verlag {KG}},
    }
  • D. J. Strauss, Adapted Filter Banks and Support Vector Architectures: Hybrid Approaches to Machine Learning, Berlin, Germany: Logos-Verlag, 2002.
    [BibTeX]
    @book{straea2002,
      author = {Strauss, D. J.},
      title = {Adapted Filter Banks and Support Vector Architectures: Hybrid Approaches to Machine Learning},
      publisher = {Logos-Verlag},
      address = {Berlin, Germany},
      year = {2002}
    }
  • W. Delb, D. J. Strauss, and P. K. Plinkert, "Binaural evozierte Potentiale bei Kindern und Erwachsenen im Zeit- und Zeit-Frequenzbereich," in Deutsche Gesellschaft für Audiologie, Fünfte Jahrestagung, 2002.
    [BibTeX]
    @InProceedings{delbea2002b,
      author    = {Delb, W. and Strauss, D. J. and Plinkert, P. K.},
      booktitle = {Deutsche Gesellschaft f\"{u}r Audiologie, F\"{u}nfte Jahrestagung},
      title     = {Binaural evozierte Potentiale bei Kindern und Erwachsenen im Zeit- und Zeit-Frequenzbereich},
      year      = {2002},
    }
  • D. J. Strauss, "Signal Processing and Computational Intelligence in Medical Diagnostics," in Proc 6th WMSCI 2002, 2002, p. 505-526 and 588-593.
    [BibTeX]
    @InProceedings{straea2002b,
      author    = {Strauss, D. J.},
      booktitle = {Proc 6th WMSCI 2002},
      title     = {Signal Processing and Computational Intelligence in Medical Diagnostics},
      year      = {2002},
      pages     = {505-526 and 588-593},
    }
  • D. J. Strauss, W. Delb, and P. K. Plinkert, "Detection of Binaural Interaction in Auditory Brainstem Responses by Morphological Local Discriminant Bases," in Proc EMBEC 2002 (3), 2002, pp. 616-617.
    [BibTeX]
    @inproceedings{straea2002c,
      author = {Strauss, D. J. and Delb, W. and Plinkert, P. K.},
      title = {Detection of Binaural Interaction in Auditory Brainstem Responses by Morphological Local Discriminant Bases},
      booktitle = {Proc EMBEC 2002 (3)},
      pages = {616-617},
      year = {2002}
    }

2001

  • D. J. Strauss, J. Jung, A. Rieder, and Y. Manoli, "Classification of Endocardial Electrograms Using Adapted Wavelet Packets and Neural Networks," Annals of Biomedical Engineering, vol. 29, iss. 6, pp. 483-492, 2001. doi:10.1114/1.1376409
    [BibTeX]
    @Article{straea2001,
      author    = {Strauss, D. J. and Jung, J. and Rieder, A. and Manoli, Y.},
      journal   = {Annals of Biomedical Engineering},
      title     = {Classification of Endocardial Electrograms Using Adapted Wavelet Packets and Neural Networks},
      year      = {2001},
      month     = {jun},
      number    = {6},
      pages     = {483--492},
      volume    = {29},
      doi       = {10.1114/1.1376409},
      publisher = {Springer Science and Business Media {LLC}},
    }
  • D. J. Strauss, G. Steidl, and J. Jung, "Arrhythmia detection using signal-adapted wavelet preprocessing for support vector machines," in Computers in Cardiology 2001. Vol.28 (Cat. No.01CH37287), 2001, pp. 497-501. doi:10.1109/cic.2001.977701
    [BibTeX] [Abstract]
    Rate based arrhythmia recognition algorithms in implantable cardioverter-defibrillators are of limited reliability in some clinical situations. Here the inclusion of morphological features of endocardial electrograms can improve the performance. In this study, we present a coupled signal-adapted wavelet-support vector machine (SVM) arrhythmia detection scheme. Within the scope of an electrophysiological examination, data segments were recorded during normal sinus rhythm (NSR) and ventricular tachycardia (VT). Consecutive beats were selected as morphological activation patterns of NSR and VT. These patterns were represented by their multilevel concentrations. For this, a signal-adapted and highly efficient lattice structure based wavelet decomposition technique was employed which maximizes the class separability and takes the final classification of NSR and VT by SVMs with radial compactly supported kernels into account. In an automated analysis of an independent test-set, our hybrid scheme outperformed other methods and classified all patterns correctly without overlap.
    @InProceedings{straea2001b,
      author    = {Strauss, D. J. and Steidl, G. and Jung, J.},
      booktitle = {Computers in Cardiology 2001. Vol.28 (Cat. No.01CH37287)},
      title     = {Arrhythmia detection using signal-adapted wavelet preprocessing for support vector machines},
      year      = {2001},
      editor    = {Murray, A. and Swiryn, S.},
      pages     = {497-501},
      publisher = {{IEEE}},
      abstract  = {Rate based arrhythmia recognition algorithms in implantable cardioverter-defibrillators are of limited reliability in some clinical situations. Here the inclusion of morphological features of endocardial electrograms can improve the performance. In this study, we present a coupled signal-adapted wavelet-support vector machine (SVM) arrhythmia detection scheme. Within the scope of an electrophysiological examination, data segments were recorded during normal sinus rhythm (NSR) and ventricular tachycardia (VT). Consecutive beats were selected as morphological activation patterns of NSR and VT. These patterns were represented by their multilevel concentrations. For this, a signal-adapted and highly efficient lattice structure based wavelet decomposition technique was employed which maximizes the class separability and takes the final classification of NSR and VT by SVMs with radial compactly supported kernels into account. In an automated analysis of an independent test-set, our hybrid scheme outperformed other methods and classified all patterns correctly without overlap.},
      doi       = {10.1109/cic.2001.977701},
    }

2000

  • J. Jung, D. J. Strauss, S. Siaplaouras, A. Buob, T. Sinnwell, Y. Manoli, H. Schieffer, and A. Heisel, "Detektion ventrikulärer Tachykardien durch Analyse des rechtsventrikulären bipolaren Elektrogrammes," in Jahrestagung der DGfK-HKF, 2000.
    [BibTeX]
    @InProceedings{jungea1998j,
      author    = {Jung, J. and Strauss, D. J. and Siaplaouras, S. and Buob, A. and Sinnwell, T. and Manoli, Y. and Schieffer, H. and Heisel, A.},
      booktitle = {Jahrestagung der DGfK-HKF},
      title     = {Detektion ventrikul\"{a}rer Tachykardien durch Analyse des rechtsventrikul\"{a}ren bipolaren Elektrogrammes},
      year      = {2000},
    }
  • D. J. Strauss, J. Jung, and A. Rieder, "Recognition of antegrade and retrograde atrial activation patterns using hybrid wavelet neural network schemes," in Computers in Cardiology 2000. Vol.27 (Cat. 00CH37163), 2000, pp. 545-549. doi:10.1109/cic.2000.898579
    [BibTeX] [Abstract]
    Currently used arrhythmia recognition algorithms in implantable cardioverter-defibrillators often fail in the discrimination of ventricular tachycardia with 1:1 retrograde conduction from sinus tachycardia. As new approach to solve this problem, we have developed a hybrid wavelet-neural network scheme for a recognition of antegrade atrial activation (AA) and retrograde atrial activation (RA) patterns in endocardial electrograms (EEs). Bipolar EEs representing AA and RA were obtained during an electrophysiological examination. Consecutive beats within data segments of 10 s duration were selected. Adapted wavelet packet decompositions were applied to extract discriminating scale features in selected beats representing AA and RA. A feed forward neural network was utilized for classifying the activation patterns based on the extracted feature vectors. With the developed hybrid wavelet-neural network scheme a recognition of all analyzed AA and RA episodes was achieved.
    @InProceedings{straea2000,
      author    = {Strauss, D. J. and Jung, J. and Rieder, A.},
      booktitle = {Computers in Cardiology 2000. Vol.27 (Cat. 00CH37163)},
      title     = {Recognition of antegrade and retrograde atrial activation patterns using hybrid wavelet neural network schemes},
      year      = {2000},
      editor    = {Murray, A. and Swiryn, S.},
      pages     = {545-549},
      publisher = {{IEEE}},
      abstract  = {Currently used arrhythmia recognition algorithms in implantable cardioverter-defibrillators often fail in the discrimination of ventricular tachycardia with 1:1 retrograde conduction from sinus tachycardia. As new approach to solve this problem, we have developed a hybrid wavelet-neural network scheme for a recognition of antegrade atrial activation (AA) and retrograde atrial activation (RA) patterns in endocardial electrograms (EEs). Bipolar EEs representing AA and RA were obtained during an electrophysiological examination. Consecutive beats within data segments of 10 s duration were selected. Adapted wavelet packet decompositions were applied to extract discriminating scale features in selected beats representing AA and RA. A feed forward neural network was utilized for classifying the activation patterns based on the extracted feature vectors. With the developed hybrid wavelet-neural network scheme a recognition of all analyzed AA and RA episodes was achieved.},
      doi       = {10.1109/cic.2000.898579},
    }
  • J. Jung, D. J. Strauss, S. Siaplaouras, A. Buob, T. Sinnwell, Y. Manoli, H. Schieffer, and A. Heisel, "Wavelet Analysis of Bipolar Endocardial Electrograms for Morphology Based Detection of Ventricular Tachycardias," in Computers in Cardiology 2000. Vol.27 (Cat. 00CH37163), 2000, pp. 347-351. doi:10.1109/cic.2000.898528
    [BibTeX] [Abstract]
    Morphology based detection criteria may increase the specificity of the detection of ventricular tachycardia (VT) in implantable cardioverter-defibrillators. The aim of the study was to create a VT detection algorithm using the wavelet transform based morphology of bipolar right ventricular electrograms (EGM). EGM were obtained during an electrophysiological study in patients (P) with inducible monomorphic VT. The wavelet description of a template EGM during normal sinus rhythm (NSR) or atrial fibrillation (AF) characterized by 7 wavelet parameters (WP) was compared to EGM under analysis. For discrimination of NSR/AF and VT, the difference of WP was considered. Discrimination of VT from NSR/AF was achieved in all P with 100% accuracy. The description of the morphology of EGM in the wavelet domain seems to be a feasible tool for discrimination of NSR or AF from VT. The incorporation of this algorithm in modern ICD-systems might improve automated arrhythmia recognition.
    @InProceedings{jungea2000,
      author    = {Jung, J. and Strauss, D. J. and Siaplaouras, S. and Buob, A. and Sinnwell, T. and Manoli, Y. and Schieffer, H. and Heisel, A.},
      booktitle = {Computers in Cardiology 2000. Vol.27 (Cat. 00CH37163)},
      title     = {Wavelet Analysis of Bipolar Endocardial Electrograms for Morphology Based Detection of Ventricular Tachycardias},
      year      = {2000},
      editor    = {Murray, A. and Swiryn, S.},
      pages     = {347-351},
      publisher = {{IEEE}},
      abstract  = {Morphology based detection criteria may increase the specificity of the detection of ventricular tachycardia (VT) in implantable cardioverter-defibrillators. The aim of the study was to create a VT detection algorithm using the wavelet transform based morphology of bipolar right ventricular electrograms (EGM). EGM were obtained during an electrophysiological study in patients (P) with inducible monomorphic VT. The wavelet description of a template EGM during normal sinus rhythm (NSR) or atrial fibrillation (AF) characterized by 7 wavelet parameters (WP) was compared to EGM under analysis. For discrimination of NSR/AF and VT, the difference of WP was considered. Discrimination of VT from NSR/AF was achieved in all P with 100% accuracy. The description of the morphology of EGM in the wavelet domain seems to be a feasible tool for discrimination of NSR or AF from VT. The incorporation of this algorithm in modern ICD-systems might improve automated arrhythmia recognition.},
      doi       = {10.1109/cic.2000.898528},
    }

1999

  • D. J. Strauss, T. Sinnwell, A. Rieder, Y. Manoli, and J. Jung, "A Promising Approach to Morphological Endocardial Signal Discriminations: Adapted Multiresolution Signal Decompositions," Applied Signal Processing, vol. 6, iss. 4, pp. 182-193, 1999. doi:10.1007/s005299970004
    [BibTeX] [Abstract]
    A major challenge for currently used algorithms in dual-chamber implantable cardioverter-defibrillators is the discrimination of ventricular tachycardias with 1:1 retrograde conduction from sinus tachycardia. Here the morphology of endocardial electrograms can be used to discriminate the physiological from the pathological state of the heart. Recently, wavelet-type multiresolution decompositions have been proposed for the detection of cardiac arrhythmias. However, the choice of appropriate wavelets used for electrogram decompositions still remains an issue. The aim of the presented paper is to assess adapted multiresolution signal decompositions of atrial endocardial electrograms as a new morphological analysis tool for a rate-independent identification of tachyarrhythmias. For the adaptation we used a library of discrete-time wavelets generated by a completely parameterised lattice structure. The results presented show that the proposed discrimination scheme is effective and promising for a morphological discrimination of endocardial electrograms.
    @Article{straea1999,
      author    = {Strauss, D. J. and Sinnwell, T. and Rieder, A. and Manoli, Y. and Jung, J.},
      journal   = {Applied Signal Processing},
      title     = {A Promising Approach to Morphological Endocardial Signal Discriminations: Adapted Multiresolution Signal Decompositions},
      year      = {1999},
      month     = {dec},
      number    = {4},
      pages     = {182--193},
      volume    = {6},
      abstract  = {A major challenge for currently used algorithms in dual-chamber implantable cardioverter-defibrillators is the discrimination of ventricular tachycardias with 1:1 retrograde conduction from sinus tachycardia. Here the morphology of endocardial electrograms can be used to discriminate the physiological from the pathological state of the heart. Recently, wavelet-type multiresolution decompositions have been proposed for the detection of cardiac arrhythmias. However, the choice of appropriate wavelets used for electrogram decompositions still remains an issue. The aim of the presented paper is to assess adapted multiresolution signal decompositions of atrial endocardial electrograms as a new morphological analysis tool for a rate-independent identification of tachyarrhythmias. For the adaptation we used a library of discrete-time wavelets generated by a completely parameterised lattice structure. The results presented show that the proposed discrimination scheme is effective and promising for a morphological discrimination of endocardial electrograms.},
      doi       = {10.1007/s005299970004},
      keywords  = {Adapted multiresolution decompositions,Endocardial electrograms,Filter banks,Wavelets},
      publisher = {Springer Science and Business Media {LLC}},
    }

1998

  • J. Jung, G. Hohenberg, D. J. Strauss, A. Heisel, H. Schieffer, and R. Fries, "Discrimination of Sinus Rhythm, Atrial Flutter, and Atrial Fibrillation Using Bipolar Endocardial Signals," Journal of Cardiovascular Electrophysiology, vol. 9, iss. 7, pp. 689-695, 1998. doi:10.1111/j.1540-8167.1998.tb00955.x
    [BibTeX] [Abstract]
    Introduction: Analysis of endocardial signals obtained from an electrode located in the right atrium as realized in newly designed dual chamber, implantable cardioverter defibrillators might be used to provide additional therapeutic options, such as overdrive pacing or low-energy atrial cardioversion for the treatment of concomitant atrial flutter (AFL) or atrial fibrillation (AF). Therefore, we developed a computer algorithm for discrimination of normal sinus rhythm (NSR), AFL, and AF that may lead to adequate differential therapy of atrial tachyarrhythmias in an automated mode. Methods and Results: During an electrophysiologic study, bipolar endocardial signals from the high right atrium were obtained in 28 patients during sustained AFL or AF and after restoration of NSR. A total of 286 data segments of 5-second duration were recorded (NSR: 96, AFL: 86, AF: 104). Mean atrial cycle length (MCL), standard deviation of mean atrial cycle length (SDCL), and index of irregularity (IR), defined as the ratio between MCL and SDCL, were calculated for each data segment. A cutoff of 315 msec for MCL allowed discrimination of NSR from atrial tachyarrhythmias with 100% sensitivity and specificity. For discrimination of AF from AFL by using SDCL, a cutoff value of 11.5 msec led to a sensitivity of 99% and a specificity of 90%. Best discrimination of AF from AFL was found for the criterion IR ≤ 7.5%, resulting in a sensitivity of 100% with a specificity of 95% for AF detection. Conclusion: The investigated algorithm provides discrimination of NSR, AFL, and AF with high sensitivity and specificity. Incorporation of this algorithm in an implantable automated antitachycardia device may lead to adequate differential therapy in patients suffering from spontaneous episodes of AF and AFL.
    @Article{jungea1998,
      author    = {Jung, J. and Hohenberg, G. and Strauss, D. J. and Heisel, A. and Schieffer, H. and Fries, R.},
      journal   = {Journal of Cardiovascular Electrophysiology},
      title     = {{D}iscrimination of {S}inus {R}hythm, {A}trial {F}lutter, and {A}trial {F}ibrillation {U}sing {B}ipolar {E}ndocardial {S}ignals},
      year      = {1998},
      issn      = {1045-3873},
      month     = jul,
      number    = {7},
      pages     = {689--695},
      volume    = {9},
      abstract  = {Introduction: Analysis of endocardial signals obtained from an electrode located in the right atrium as realized in newly designed dual chamber, implantable cardioverter defibrillators might be used to provide additional therapeutic options, such as overdrive pacing or low-energy atrial cardioversion for the treatment of concomitant atrial flutter (AFL) or atrial fibrillation (AF). Therefore, we developed a computer algorithm for discrimination of normal sinus rhythm (NSR), AFL, and AF that may lead to adequate differential therapy of atrial tachyarrhythmias in an automated mode. Methods and Results: During an electrophysiologic study, bipolar endocardial signals from the high right atrium were obtained in 28 patients during sustained AFL or AF and after restoration of NSR. A total of 286 data segments of 5-second duration were recorded (NSR: 96, AFL: 86, AF: 104). Mean atrial cycle length (MCL), standard deviation of mean atrial cycle length (SDCL), and index of irregularity (IR), defined as the ratio between MCL and SDCL, were calculated for each data segment. A cutoff of 315 msec for MCL allowed discrimination of NSR from atrial tachyarrhythmias with 100% sensitivity and specificity. For discrimination of AF from AFL by using SDCL, a cutoff value of 11.5 msec led to a sensitivity of 99% and a specificity of 90%. Best discrimination of AF from AFL was found for the criterion IR ≤ 7.5%, resulting in a sensitivity of 100% with a specificity of 95% for AF detection. Conclusion: The investigated algorithm provides discrimination of NSR, AFL, and AF with high sensitivity and specificity. Incorporation of this algorithm in an implantable automated antitachycardia device may lead to adequate differential therapy in patients suffering from spontaneous episodes of AF and AFL.},
      doi       = {10.1111/j.1540-8167.1998.tb00955.x},
      keywords  = {Arrhytmia detection,Atrial fibrillation,Atrial flutter},
      publisher = {Wiley},
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Assessment of Intersignal Variability for Discrimination of Atrial Fibrillation from Atrial Flutter," Pacing and Clinical Electrophysiology, vol. 21, iss. 11, pp. 2426-2430, 1998. doi:10.1111/j.1540-8159.1998.tb01195.x
    [BibTeX] [Abstract]
    The analysis of endocardial signals obtained from an electrode located in the right atrium enabled by new dual chamber implantable cardioverter defibrillators may be helpful to provide additional therapies such as overdrive pacing or low energy atrial cardioversion for the treatment of concomitant atrial flutter (AFL) or atrial fibrillation (AF). Algorithms for discrimination of atrial tachyarrhythmias based on rate counting are of limited efficacy. The aim of this study was to assess the intersignal variability by using fast discrete wavelet transforms (FDWT) as a new method of discrimination of AF from AFL. Patients with spontaneous episodes of AF/AFL or patients who developed AF/AFL during an electrophysiological study were studied. The endocardial signals were recorded from the high right atrium using a transvenous 5 Fr bipolar electrode catheter (interelectrode spacing: 1 cm). The signals were digitized (2 kHz, 12-bit resolution) after amplification and filtering (40-500 Hz). Within data segments of 10-second duration, 25 consecutive signals were selected and normalized and FDWT was applied. Standard deviations of the wavelet coefficients (SD) from coarse scales (scale 4-8) were calculated. A total of 94 data segments (AF: 52, AFL: 42) from 28 patients were analyzed. SD at each considered scale was higher for AF than for AFL (P < 0.001). SD at scale 8 discriminated between AF from AFL with 100% sensitivity and specificity. We conclude that assessment of intersignal variability of bipolar endocardial recordings using FDWT is an effective method for the discrimination of AF from AFL. The implementation of this tool in a discrimination algorithm of an implantable device may help provide the appropriate differential therapy for atrial tachyarrhythmias.
    @Article{jungea1998b,
      author    = {Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      journal   = {Pacing and Clinical Electrophysiology},
      title     = {Assessment of Intersignal Variability for Discrimination of Atrial Fibrillation from Atrial Flutter},
      year      = {1998},
      issn      = {0147-8389},
      month     = {nov},
      number    = {11},
      pages     = {2426--2430},
      volume    = {21},
      abstract  = {The analysis of endocardial signals obtained from an electrode located in the right atrium enabled by new dual chamber implantable cardioverter defibrillators may be helpful to provide additional therapies such as overdrive pacing or low energy atrial cardioversion for the treatment of concomitant atrial flutter (AFL) or atrial fibrillation (AF). Algorithms for discrimination of atrial tachyarrhythmias based on rate counting are of limited efficacy. The aim of this study was to assess the intersignal variability by using fast discrete wavelet transforms (FDWT) as a new method of discrimination of AF from AFL. Patients with spontaneous episodes of AF/AFL or patients who developed AF/AFL during an electrophysiological study were studied. The endocardial signals were recorded from the high right atrium using a transvenous 5 Fr bipolar electrode catheter (interelectrode spacing: 1 cm). The signals were digitized (2 kHz, 12-bit resolution) after amplification and filtering (40-500 Hz). Within data segments of 10-second duration, 25 consecutive signals were selected and normalized and FDWT was applied. Standard deviations of the wavelet coefficients (SD) from coarse scales (scale 4-8) were calculated. A total of 94 data segments (AF: 52, AFL: 42) from 28 patients were analyzed. SD at each considered scale was higher for AF than for AFL (P < 0.001). SD at scale 8 discriminated between AF from AFL with 100% sensitivity and specificity. We conclude that assessment of intersignal variability of bipolar endocardial recordings using FDWT is an effective method for the discrimination of AF from AFL. The implementation of this tool in a discrimination algorithm of an implantable device may help provide the appropriate differential therapy for atrial tachyarrhythmias.},
      doi       = {10.1111/j.1540-8159.1998.tb01195.x},
      keywords  = {Arrhythmia detection,Atrial fibrillation,Atrial flutter,Wavelet analysi},
      publisher = {Wiley},
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Discrimination of Atrial Fibrillation and Atrial Flutter Using the Discrete Wavelet Transform," in Eur Heart J, 1998, p. 370.
    [BibTeX]
    @inproceedings{jungea1998c,
      author = {Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      title = {Discrimination of Atrial Fibrillation and Atrial Flutter Using the Discrete Wavelet Transform},
      booktitle = {Eur Heart J},
      pages = {370},
      year = {1998},
      volume = {12}
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "A New Method for the Discrimination of Antegrade and Retrograde Atrial Activation," in Pacing Clin Electrophysiol, 1998, p. 918.
    [BibTeX]
    @inproceedings{jungea1998e,
      author={Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      title={A New Method for the Discrimination of Antegrade and Retrograde Atrial Activation},
      booktitle = {Pacing Clin Electrophysiol},
      pages = {918},
      volume = {21},
      year = {1998}
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Feasibility of Wavelet Transforms For Discrimination of Antegrade form Retrograde Atrial Activation," in Ann Noninvasive Electrocardiol, 1998, p. 58.
    [BibTeX]
    @inproceedings{jungea1998f,
      author = {Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      title = {Feasibility of Wavelet Transforms For Discrimination of Antegrade form Retrograde Atrial Activation},
      booktitle = {Ann Noninvasive Electrocardiol},
      pages = {58},
      volume = {3},
      year = {1998}
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Discrimination of Antegrade and Retrograde Atrial Activation by Using Wavelet Transforms," in Archives des Maladies du Coeur et des Vaisseaux, 1998, p. 269.
    [BibTeX]
    @inproceedings{jungea1998g,
      author = {Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      title = {Discrimination of Antegrade and Retrograde Atrial Activation by Using Wavelet Transforms},
      booktitle = {Archives des Maladies du Coeur et des Vaisseaux},
      pages = {269},
      volume = {91},
      year = {1998}
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Analysis of Bipolar Endocardial Signals for Discrimination of Antegrade and Retrograde Atrial Actication," in Eur Heart J, 1998, p. 369.
    [BibTeX]
    @inproceedings{jungea1998h,
      author = {Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      title = {Analysis of Bipolar Endocardial Signals for Discrimination of Antegrade and Retrograde Atrial Actication},
      booktitle = {Eur Heart J},
      pages = {369},
      volume = {12},
      year = {1998}
    }
  • D. J. Strauss, J. Jung, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Endocardial Signal Processing Using Discrete Wavelet Transforms," in Ann Noninvasive Electrocardiol, 1998, p. 58.
    [BibTeX]
    @inproceedings{straea1998,
      author = {Strauss, D. J. and Jung, J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      title = {Endocardial Signal Processing Using Discrete Wavelet Transforms},
      booktitle = {Ann Noninvasive Electrocardiol},
      pages = {58},
      volume = {3},
      year = {1998},
    }
  • J. Jung, D. J. Strauss, T. Sinnwell, G. Hohenberg, R. Fries, H. Wern, H. Schieffer, and A. Heisel, "Identification of ventricular tachycardias by means of fast wavelet analysis," in Computers in Cardiology 1998. Vol. 25 (Cat. No.98CH36292), 1998, pp. 21-24. doi:10.1109/cic.1998.731699
    [BibTeX] [Abstract]
    Discrimination of ventricular tachycardias at slow rate from sinus tachycardia still remains a challenge for implantable antitachycardia devices. It was the purpose of this study to assess the feasibility of endocardial signal processing using fast wavelet analysis (FWA) as a novel approach for discrimination of ventricular tachycardia (VT) and normal sinus rhythm (NSR). During an electrophysiological study, bipolar endocardial signals were obtained from the right ventricle in patients with known monomorphic VT. FWA was applied to single endocardial activations. The distribution of energy in the time-scale domain clearly discriminated between endocardial signals obtained during NSR and VT in each particular patient when using an individually adjusted wavelet. In patients with multiple VTs, identification of each VT with different morphology was also achievable.
    @InProceedings{jungea1998d,
      author    = {Jung, J. and Strauss, D. J. and Sinnwell, T. and Hohenberg, G. and Fries, R. and Wern, H. and Schieffer, H. and Heisel, A.},
      booktitle = {Computers in Cardiology 1998. Vol. 25 (Cat. No.98CH36292)},
      title     = {Identification of ventricular tachycardias by means of fast wavelet analysis},
      year      = {1998},
      editor    = {Murray, A. and Swiryn, S.},
      pages     = {21-24},
      publisher = {{IEEE}},
      abstract  = {Discrimination of ventricular tachycardias at slow rate from sinus tachycardia still remains a challenge for implantable antitachycardia devices. It was the purpose of this study to assess the feasibility of endocardial signal processing using fast wavelet analysis (FWA) as a novel approach for discrimination of ventricular tachycardia (VT) and normal sinus rhythm (NSR). During an electrophysiological study, bipolar endocardial signals were obtained from the right ventricle in patients with known monomorphic VT. FWA was applied to single endocardial activations. The distribution of energy in the time-scale domain clearly discriminated between endocardial signals obtained during NSR and VT in each particular patient when using an individually adjusted wavelet. In patients with multiple VTs, identification of each VT with different morphology was also achievable.},
      doi       = {10.1109/cic.1998.731699},
    }