Recognition of Simulated Telephone Speech by Cochlear Implant Users

Abstract

To evaluate cochlear implant users' understanding of telephone speech. Telephone speech was simulated by band-limiting broadband speech stimuli. Multitalker vowel, consonant, and sentence recognition was measured for both simulated telephone speech and broadband speech in 10 postlingually deafened adult cochlear implant users. The study was approved by the St. Vincent's Hospital institutional review board, and signed, informed consent was obtained from all participants. There was no significant difference in vowel recognition scores between broadband and telephone speech. However, mean consonant and sentence recognition scores were significantly poorer with telephone speech. The limited telephone bandwidth significantly reduced cochlear implant users' understanding of telephone speech. The effect of band-limited speech was highly variable, suggesting that the contribution of high-frequency information to speech recognition varied significantly among the cochlear implant users.