Cochlear implants are small, electronic devices
that can be surgically implanted to enable profoundly deaf children and adults
who are not helped by traditional hearing aids to hear better. The May 19,
2004, issue of JAMA includes an article about cochlear
implantation in children, and the May 2004 issue of the Archives of Otolaryngology Head & Neck Surgery is a theme issue
devoted to this topic.
Sound waves funneled into the ear cause the tympanic membrane (eardrum) to vibrate.
These vibrations are transmitted across a bridge formed by 3 small bones to the cochlea of the inner
The fluid-filled cochlea contains
hair cells that sense vibrations transmitted through the fluid.
The hair cells trigger impulses in the auditory (hearing) nerve that transmit to the brain where they are
interpreted as sound.
Most profound deafness is sensorineural—there
is damage to the sensitive and vulnerable hair cells in the cochlea so that
vibrations in the cochlea cannot be transmitted. Cochlear implants can restore
hearing by bypassing the hair cells and stimulating the auditory nerve directly.
After the patient recovers from surgery for about
a month, the speech processor is placed and then adjusted as hearing improves
in a process called mapping. As hearing gets better,
further adjustments are made over time.
Training with speech therapists or a teacher of
the hearing-impaired will help patients learn how to use the cochlear implant.
Children in their formative years need to be taught to understand new sounds
and their meanings and to translate them into speech and language.
American Speech-Language-Hearing Association1-
800/638-8255 TTY: 1- 800/498-2071 http://www.asha.org
Cochlear Implant Association, Inchttp://www.cici.org
Self-Help for Hard of Hearing PeopleVoice:
301/657-2248 TTY: 301/657-2249 http://www.shhh.org
To find this and other JAMA Patient Pages, go to the Patient Page link
on JAMA's Web site at http://www.jama.com.
A Patient Page on adult hearing loss was published in the April 16, 2003,
Sources: Cochlear Implant Association, Inc, National Institute on Deafness
and Other Communication Disorders, American Speech-Language-Hearing Association
The JAMA Patient Page is a public service of JAMA. The information and recommendations appearing on this page
are appropriate in most instances, but they are not a substitute for medical
diagnosis. For specific information concerning your personal medical condition, JAMA suggests that you consult your physician. This page
may be photocopied noncommercially by physicians and other health care professionals
to share with patients. Any other print or online reproduction is subject
to AMA approval. To purchase bulk reprints, call 718/946-7424.
Parmet S, Lynm C, Glass RM. Cochlear Implants. JAMA. 2004;291(19):2398. doi:10.1001/jama.291.19.2398