Sound Localization by Cochlear Implant Users

ABSTRACT

Binaural cochlear implantation has become a fairly common phenomenon for adults and children. In addition, many monaural cochlear implant recipients use a hearing aid in the unimplanted ear. One of the rationales for these bilateral fittings is to improve localization of sound sources, at least in the horizontal plane. Several studies have been published on localization using a remarkably wide range of stimuli, speaker arrays, and measurement variables. This article attempts to sort through the variables and find commonalities in the research. It is clear that the majority of adults with bilateral cochlear implants are much better at horizontal localization with two implants compared with one, but their abilities do not reach those of normal-hearing listeners. The localization results for children and for bimodal (cochlear implant in one ear, hearing aid in the other) listeners are less clear, with some improvement over monaural listening, but not for all subjects.

KEYWORDS

Cochlear implant - binaural - bimodal - localization

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