Abstract:
Acoustic characteristics of speech production produced with and without auditory feedback from a multichannel cochlear implant was examined in eleven French speaking children with profound hearing losses. Subjects produced five repetitions of stimuli designed to contrast voice-onset times and vowel formant frequencies. Samples were collected with the implant turned on and after a 10-min period of the implant turned off. Stimuli were audio recorded, low-pass filtered, and digitized at a 10-kHz rate. VOT's and formant frequencies were measured using Cspeech software. VOTs for the bilabial cognates, /b/ and /p/, revealed considerable overlap in temporal values when no auditory feedback was available. During conditions providing auditory feedback, VOTs shifted to more nearly normal values with minimal overlap. Vowel formant frequencies also shifted as a function of implant status; however, the patterns of shift differed across subjects and across feedback conditions. Data suggest pediatric users of cochlear implants are able to use auditory feedback to adjust their speech production; however, the relationships between auditory conditions and speech acoustics appear complex. [Work supported by the Ministere de la Sante and a visiting research scholar award from the University of Montpellier.]