Evaluation of cues for horizontal-plane localization with bilateral cochlear implants

Authors

  • Tamás Harczos Fraunhofer Institute for Digital Media Technology IDMT, Ehrenbergstr. 31, 98693 Ilmenau, Germany; Institute for Media Technology, Faculty of Electrical Engineering and Information Technology, Ilmenau University of Technology, Helmholtzplatz 2, 98693 Ilmenau, Germany
  • Stephan Werner Institute for Media Technology, Faculty of Electrical Engineering and Information Technology, Ilmenau University of Technology, Helmholtzplatz 2, 98693 Ilmenau, Germany
  • Gero Szepannek Department of Statistics, University Dortmund, Vogelpothsweg 87, 44227 Dortmund, Germany
  • Karlheinz Brandenburg Fraunhofer Institute for Digital Media Technology IDMT, Ehrenbergstr. 31, 98693 Ilmenau, Germany; Institute for Media Technology, Faculty of Electrical Engineering and Information Technology, Ilmenau University of Technology, Helmholtzplatz 2, 98693 Ilmenau, Germany

Abstract

Over the past decade, cochlear implants (CIs) have become a widely accepted alternative for treatment of people with severe to profound hearing loss. Now, bilateral implantation is offered to a growing number of individuals in order to provide bene ts of binaural hearing. One of these bene ts is the ability to localize sound sources. Current CIs are not able to fully transmit the spectro-temporal information that is available for normal-hearing listeners. Experiments have shown however, that even in the absence of the ne temporal structures, CI-users are able to localize sounds in the horizontal-plane to some extent. We present a simulation study dealing with possible causes of the limited localization capabilities of CI-subjects. Concentrating on the most commonly used strategy, advanced combination encoder (ACE), we elaborate on the effects of left-right device asynchrony and that of changing the pulse rate and the number of selected spectral bands. We simulate the CI-processing up to the actuation of the electrodes complemented with a model of current spreading in the endolymph. Relying on this data, we verify localization possibilities based on interaural time differences using a generalized cross-correlation method.

References

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Additional Files

Published

2009-12-15

How to Cite

Harczos, T., Werner, S., Szepannek, G., & Brandenburg, K. (2009). Evaluation of cues for horizontal-plane localization with bilateral cochlear implants. Proceedings of the International Symposium on Auditory and Audiological Research, 2, 37–46. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2009-04

Issue

Vol. 2 (2009): Binaural Processing and Spatial Hearing

Section

2009/1. Physiological measures and models of binaural hearing

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