MSB Online Seminar: Influence of interaural stimulation timing on binaural hearing in normal hearing listeners and bimodal CI/HA users

Titel: Influence of interaural stimulation timing on binaural hearing in normal hearing listeners and bimodal CI/HA users

Sprecherin:  Julian Angermeier,  Arbeitsgruppe „Bioanaloge Informationsverarbeitung” (Prof. Werner Hemmert)

Datum und Uhrzeit: Dienstag, 15. Dezember 2020, 13:00 Uhr

Abstract:
In bimodal users of cochlear implants (CI) in one ear and a hearing aid (HA) in the contralateral ear, different signal pathways inflict a static time difference between both ears. This time difference has been shown to be in the order of several milliseconds and is further referred to as device delay mismatch. Since the auditory system relies on precise timing information for binaural tasks such as sound localization and spatial release from masking, this device delay mismatch is hypothesized to have detrimental effects on binaural hearing. To investigate these effects psychoacoustic experiments were conducted in normal hearing listeners as well as in bimodal CI/HA users. In bimodal CI/HA users this device delay mismatch was reduced by delaying the faster modality (i.e. the CI) with a programmable delay line. Sound localization tests were conducted with a reduced device delay mismatch showing significant improvements in sound localization accuracy compared to test conditions without compensation for the device delay mismatch. Further in normal hearing subjects, speech tests revealed a significant effect of a rising device delay mismatch on spatial release from masking. These findings suggest the importance of temporal alignment in signal processing in asymmetric treatment of hearing loss.