Across-electrode processing in CI users: a strongly etiology dependent task

Authors

  • Stefan Zirn Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig-Maximilians-University Munich, Germany IMETUM, Bio-Inspired Information Processing, Technische Universität München, Germany
  • John-Martin Hempel Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig-Maximilians-University Munich, Germany
  • Maria Schuster Department of Otorhinolaryngology, Head and Neck Surgery, Ludwig-Maximilians-University Munich, Germany
  • Werner Hemmert IMETUM, Bio-Inspired Information Processing, Technische Universität München, Germany

Abstract

To investigate across-electrode processing in cochlear-implant (CI) users, we established an experimental setup that allows measuring comodulation masking release (CMR) using controlled electrical stimulation of auditory nerve fibers. In this paper we present results of a flanking-band type of CMR experiment with uncorrelated (UC) vs. comodulated (CM) masker components. To deal with the large current spread in electrical stimulation that may introduce additional masking especially in the UC condition, we now compare two different electrode configurations: proximate vs. remote alignments of flanking bands in reference to the on-signal band. Results of 18 test subjects revealed no significant difference between CMR[UC-CM] magnitudes across these two conditions (p = 0.3), whereas outcomes varied strongly across test subjects. To highlight different groups of performers, a hierarchical cluster analysis was conducted. N = 5 CI users showed no or even negative CMR. The majority of N = 9 CI users exhibited positive and significant CMR (around 3 dB). Finally, a subset of N = 4 CI users showed considerable CMR magnitudes (6-10 dB). Etiology was a good indicator for the remaining individual CMR capabilities.

References

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Zirn, S., Hempel, J.M., Schuster, M., and Hemmert, W. (2013). “Comodulation masking release induced by controlled electrical stimulation of auditory nerve fibers,” Hear. Res., 296, 60-66.

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Published

2013-12-15

How to Cite

Zirn, S., Hempel, J.-M., Schuster, M., & Hemmert, W. (2013). Across-electrode processing in CI users: a strongly etiology dependent task. Proceedings of the International Symposium on Auditory and Audiological Research, 4, 325–331. Retrieved from http://proceedings.isaar.eu/index.php/isaarproc/article/view/2013-36

Issue

Section

2013/6. New processing and fitting strategies in cochlear implants