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Updated: May 19, 2026

An Automated System for Sound Localization Testing in Hearing-Impaired Listeners
Published on: March 13, 2026
The effect of interaural differences in envelope shape on the perceived location of sounds (L)
Tom Francart1, Anneke Lenssen, Jan Wouters
1ExpORL, Department of Neurosciences, KU Leuven, O & N 2, Herestraat 49 bus 721, B-3000 Leuven, Belgium. Tom.Francart@med.kuleuven.be
Abstract:
Users of bilateral cochlear implants and a cochlear implant combined with a contralateral hearing aid are sensitive to interaural time differences (ITDs). The way cochlear implant speech processors work and differences between modalities may result in interaural differences in shape of the temporal envelope presented to the binaural system. The effect of interaural differences in envelope shape on ITD sensitivity was investigated with normal-hearing listeners using a 4 kHz pure tone modulated with a periodic envelope with a trapezoid shape in each cycle. In one ear the onset segment of the trapezoid was transformed by a power function. No effect on the just noticeable difference in ITD was found with an interaural difference in envelope shape, but the ITD for a centered percept was significantly different across envelope shape conditions.
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