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Description

A cochlear implant is a medical electronic device designed to send sound signals to the brain in order to give deaf persons a sense of hearing. It does not restore hearing, but as the NIDCD says, gives a “useful representation of sounds” allowing the user to respond to sounds in their environment and comprehend spoken conversation. It differs from hearing aids in that hearing aids only amplify sound, while the cochlear implant sends signals to the brain.

How It Works

The cochlear implant is comprised of both external and internal devices:
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  • Microphones
  • Speech Processor
  • Transmitter
Internal
  • Receiver and Stimulator
  • Electrodes

The external microphone receives sound from the outside world and the speech processor filters some of those sounds to process spoken words. The transmitter then uses electromagnetic induction to transmit power and sound signals to the internal receiver. The receiver and stimulator convert those signals into impulses, which are then sent to the electrodes that have been surgically implemented into the cochlea. This stimulates the auditory nerve and the sensations are perceived as hearing and sound by the brain.

Applications

Cochlear implants can help those who suffer from hearing loss. It can provide sound to people who “receive little or no benefit from hearing aids” (Cochlear.com). The cochlear implant is especially beneficial to those with hearing loss in both ears. The cochlear implant can help deaf persons overcome their handicap. It allows them to focus on specific sounds in loud, busy places, whereas before they could only feel vibrations. They can enjoy music, talk on the phone, and enjoy a conversation with better sentence/speech understanding. Some are even able to hear sounds for the first time after the implementation of the cochlear implant.

Those who best qualify for cochlear implants are adults with severe hearing loss in both ears. It is best if they have some auditory memory as well as speech and language skills. In children with severe hearing loss in both ears, since they are still developing, auditory memory isn’t necessary. A child with a cochlear implant has to undergo habilitation to learn to recognize sounds and develop speech skills.

Web Resources

http://www.cochlear.com/

http://www.asha.org/

http://www.hearingloss.org/content/cochlear-implants

Related Terms

  • Hearing Aid
  • Electromagnetic Induction
  • Neuroprosthetics
  • Cochlea
  • Deaf

Citations/References