title: Interaural level difference cues determine sound source localization by single-sided deaf patients fit with a cochlear implant.
abstract: In this report, we used filtered noise bands to constrain listeners' access to interaural level differences (ILDs) and interaural time differences (ITDs) in a sound source localization task. The samples of interest were listeners with single-sided deafness (SSD) who had been fit with a cochlear implant in the deafened ear (SSD-CI). The comparison samples included listeners with normal hearing and bimodal hearing, i.e., with a cochlear implant in 1 ear and low-frequency acoustic hearing in the other ear. The results indicated that (i) sound source localization was better in the SSD-CI condition than in the SSD condition, (ii) SSD-CI patients rely on ILD cues for sound source localization, (iii) SSD-CI patients show functional localization abilities within 1-3 months after device activation and (iv) SSD-CI patients show better sound source localization than bimodal CI patients but, on average, poorer localization than normal-hearing listeners. One SSD-CI patient showed a level of localization within normal limits. We provide an account for the relative localization abilities of the groups by reference to the differences in access to ILD cues.
authors.affiliation: Department of Speech and Hearing Science, Arizona State University, Tempe, Ariz., USA.
authors.forename: Michael F
authors.initials: MF
authors.lastname: Dorman
authors.forename: Daniel
authors.initials: D
authors.lastname: Zeitler
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Cook
authors.forename: Louise
authors.initials: L
authors.lastname: Loiselle
authors.forename: William A
authors.initials: WA
authors.lastname: Yost
authors.forename: George B
authors.initials: GB
authors.lastname: Wanna
authors.forename: Rene H
authors.initials: RH
authors.lastname: Gifford
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D003054:Cochlear Implants; D003463:Cues; D005260:Female; D046088:Hearing Loss, Unilateral / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013017:Sound Localization / Q000502:physiology*