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Cochlear Implants

Of the several causes of deafness, only one type-conductive deafness due to bony growths on the ossicles-can be treated with surgery. Until recent decades there was no treatment for nerve deafness, which is due to disorders in the cochlear system. In the 1980s, scientists found that if the hair cells inside the cochlea could be bypassed and the nerve cells could be stimulated directly at several places along the length of the cochlea, a patient with nerve deafness might be hear again. Cochlear implants are devices that convert sounds into electrical stimulation for nerve cells of the cochlea

What is a cochlear implant?

Initial efforts to stimulate the cochlea were not very successful. Schmeck (1984) reported how one patient, totally deaf for a year, was given an early version of the cochlear implant. He reported that his own voice sounded to him "like a bunch of Martians." He was "far from being able to understand conversational speech."

What refinements in technology are improving performance of such implants?

Since then, cochlear implants have come a long way. The most important improvement was the introduction of microprocessors: small computers located within the implant. They enhance the frequencies of sound most useful for speech and screen out less useful noise. By the 2000s the implants were very useful for improving speech perception in certain cases, although they typically required that special equipment be worn outside the body.

For examples of such products, see the following manufacturer's sites:

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Why do some people in the deaf community resent cochlear implants?

Cochlear implants are controversial in the deaf community. Many deaf parents prefer to have their children grow up in the cultural traditions of the deaf community. Sign language is just as rich and expressive as spoken language. Deaf people resent the implication that deafness is a defect that needs to be fixed. A deaf child can have a full, happy life without cochlear implants. Many deaf parents regard deafness as a birthright they do not wish to deny their child.

Parents who are not deaf themselves are more likely to want a cochlear implant for a child who is deaf. Cochlear implants can help a child speak more normally. Some children who grow up with cochlear implants endorse them; others decide to abandon the devices and participate fully in the deaf community using sign language.

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