Abstract
Recently, it has been recognized that the number of multiply handicapped children, especially those with pervasive developmental disorders, who are also hard of hearing, has been gradually increasing. To estimate the hearing threshold, in principle, behavioral observation audiometry (BOA) and/or conditioned orientation response audiometry (COR) with auditory brain responses (ABR) can also be used for multiply handicapped children as for hearing-impaired children with normal development. Periodic assessment of the hearing threshold, however, should be performed because there are cases in which the ABR threshold and the COR minimum reaction level improve with development. The auditory steady-state response (ASSR) can be expected to complement weak points of the COR and ABR, because ASSR thresholds provide objective and reliable estimations of frequency-specific hearing levels in both ears. It would seem that the primary goal of the fitting of hearing aids and of cochlear implants, particularly for multiply handicapped children, has changed nowadays. That is, interventions are thought to be successful even if the children cannot develop language skills, if they become capable of utilizing other communication media. Therefore, the purpose and efficacy of cochlear implants, which are more or less invasive, must be adequately explained to parents so as to avoid unrealistic expectations.
