Responses to short-term auditory stimulation through contralateral hearing aid use in pediatric cochlear implant users.

摘要

Binaural hearing is necessary for localization of sounds and understanding speech in the presence of background noise. Unilateral implantation is the current standard for deaf children and adults who are candidates for a cochlear implant. There is debate as to whether a listener can process sound through bimodal amplification, that is, an electrical signal from a cochlear implant in the presence of an acoustical signal from an amplification device in the contralateral ear. The present investigation focused on short-term auditory stimulation with a hearing aid in the nonimplanted ear and its effect on localization and speech discrimination in noise in pediatric cochlear implant users.; Six children with prelingual, bilateral severe-to-profound sensorineural hearing loss, who were consistent cochlear implant users for at least 6 continuous months, and who had not consistently worn a hearing aid in the nonimplanted ear since their implant surgeries participated in this study. Speech recognition and localization testing were conducted in two aided conditions, with the cochlear implant alone and with the CI and contralateral hearing aid. Testing in the bimodal condition was preceded by at least 30 minutes of intense listening, often through auditory training or speech therapy. All testing was carried out twice with no less than 2 weeks between testing sessions, in order to investigate possible fatigue and learning effects.; There were negligible fatigue and learning effects on speech perception within each subject's performance, although there was much variability across individual results. Results suggest that localization with an implant or with an implant and hearing aid may be a learning process. Even after short-term contralateral hearing aid use, the children in this study performed similarly to children in other studies who had more experience in the bimodal condition. Important considerations for listening situations where background noise may be an issue were discussed. Short-term bimodal amplification may be useful for speech therapy or auditory training sessions or in classroom settings where background noise is present. Binaural benefit on the localization test did not reach statistical significance when considering both trials. This apparent lack of binaural benefit may be due to critical periods of auditory development.