RNID: For deaf and hard of hearing people.

There are about 7,000 people in the UK with cochlear implants and the number is growing every year.

For people who get little or no benefit from a hearing aid, implants can markedly improve their ability to hear and understand speech. A review by the National Institute for Clinical Excellence shows that cochlear implants enable deaf children to learn language, speak intelligibly and perform better at school. Deaf adults are able to communicate more confidently, regain their independence, and stand a better chance of getting a worthwhile job.

A cochlear implant consists of:

  • An internal part: a receiver which is surgically implanted in the mastoid bone behind the ear, with electrodes inserted into the inner ear, or cochlea.
  • An external part: a microphone and speech processor which convert sound into an electrical signal that is sent to the electrodes in the inner ear. These then send the signal through the auditory nerve to the brain, where it is perceived as sound.

Q: What is a cochlear implant?

A: Cochlear implants provide a sensation of hearing to those who have severe to profound permanent deafness. This means that they may be able to hear some sounds, but they cannot hear all the sounds that make up human speech.

Instead of making the sound louder, like a hearing aid, the implant directly stimulates the auditory nerve (the nerve that carries sound from the cochlea to the brain) using electrical signals.

Q: How does a cochlear implant work?

A: Sound is picked up by the microphone and processed, then changed into electrical signals and passed along to the transmitter coil.

The transmitter coil sends signals, by radio wave, through the skin to the implanted receiver. The receiver sends the signals down the wire to the electrodes in the cochlea.

When the electrodes receive the signal, they make a tiny current along the auditory nerve to provide a sensation of hearing.

Now RNID want to improve this technique still further. Please read on to discover more about RNID’s research, and how you can help to change the lives of many more deaf people.