Personal Reflections on the Multichannel Cochlear Implant and a View of the FutureBy Clark, Graeme M.; Journal of Rehabilitation Research and Development, Vol. 45, No. 5, pp. 651-694
Publication Date: 2008
Article, written by one of the developers of the cochlear implant, traces its history as a method of restoring hearing. The initial discovery that hearing could be induced by the electric alternating-current stimulation of the auditory nerve is discussed, leading to the development of the multichannel cochlear implant. The components of the implant are described, including a microphone that passes signals to a small processor worn behind the ear, whereupon coded information is transmitted through the skin to the implanted unit behind the ear. The transmission stimulates the hearing nerve in the inner ear, and the responses pass to the brain where they are understood as speech. Also outlined is the development of a safe surgical procedure of implantation that avoids surgical trauma and inner-ear infection, utilizes biocompatible materials, and allows for head growth in implanted infants. The role of bilateral implants in conferring the benefits of binaural hearing is also discussed. Two challenges for future research are presented: using nanotechnology to enable the reception of high-fidelity sound, which would help deaf persons communicate in noise and enjoy music; and electroacoustic hearing, which involves implanting ears with residual low-frequency hearing and preserving that hearing, vibrating the basilar membrane to excite residual hair cells, and electrically stimulating the nerves that transmit the higher frequencies.
VA Rehabilitation Research & Development Service (Web Site: http://www.rehab.research.va.gov )
Link to text: http://www.rehab.research.va.gov/jour/08/45/5/clark.html