Changes in speech intelligibility of postlingually deaf adults after cochlear implantation.

摘要

OBJECTIVE: This study examines changes in the intelligibility of CVC words spoken by postlingually deafened adults after they have had 6 to 12 mo of experience with a cochlear implant. The hypothesis guiding the research is that the intelligibility of these speakers will improve after extended use of a cochlear implant. The paper also describes changes in CVC word intelligibility analyzed by phoneme class and by features. DESIGN: The speech of eight postlingually deaf adults was recorded before activation of the speech processors of their cochlear implants and at 6 mo and 1 yr after activation. Seventeen listeners with no known impairment of hearing completed a word identification task while listening to each implant user's speech in noise. The percent information transmitted by the speakers in their pre- and postactivation recordings was measured for 11 English consonants and eight vowels separately. RESULTS: An overall improvement in word intelligibility was observed: seven of the eight speakers showed improvement in vowel intelligibility and six speakers showed improvement in consonant intelligibility. However, the intelligibility of specific consonant and vowel features varied greatly across speakers. CONCLUSIONS: Extended use of a cochlear implant by postlingually deafened adults tends to enhance their intelligibility.