Cochlear implants

What is a cochlear implant?

A young boy with a cochlear implant playing with a tablet device

A cochlear implant is an electronic system that stimulates the hearing nerves, directly sending a sensation of sound to the brain.

Unlike a hearing aid, the individual needs an operation to place the implant in the cochlea (or inner ear) inside their head.

It uses a microphone to pick up the sound and a speech processor to deliver sound to a set of implanted electrodes in the inner ear.

A cochlear implant speech processor looks just like a hearing aid and is programmed by a specialist audiologist to provide the best possible speech perception for the individual. The coil on the processor transmits sound through the skin to an internal receiver.

Some people will have a cochlear implant for just one ear while others will have a bilateral implant, meaning that both ears are implanted. Under current guidelines, deafblind people are more likely to be offered two implants. This may help with listening in noisy rooms and with hearing where sound is coming from.

Who might benefit from cochlear implantation?

Being fitted with cochlear implants is not beneficial to all deaf and hearing impaired people as success is dependent on the individual’s type of hearing loss.

Those who may benefit are people who have a sensorineural hearing loss. This is caused by the sensitive hair cells inside the cochlea (inner ear) being damaged, or as a result of damage to the auditory nerve (the nerve that transmits sound to brain). In some cases, both may be damaged.

Anybody who thinks they may benefit from an implant should contact their GP, local Ear, Nose and Throat department or Audiology department to obtain a referral to a Cochlear Implant Centre.

What are the advantages and disadvantages of having a cochlear implant?

  • An individual can hear sounds around him or her and so can learn to react to them – for example, hearing someone approach, sounds in the environment
  • They can improve hearing for speech
  • A cochlear implant may also enable the individual to develop spoken language because they can hear their voice for the first time
  • Some people benefit more from a cochlear implant than others
  • It is difficult to predict before the operation how someone may respond to this new signal
  • Not all individuals will learn to speak
  • It may be necessary to have further operations in the future if the cochlear implant stops working inside

Points to think about

  • There is no assessment test that is carried out beforehand that will say if an individual will definitely benefit a lot or not.
  • Progress may be slow as it can take time for a deafblind individual to learn to use the sound information provided by the cochlear implant, particularly as they may often be unable to make use of lip-reading cues.
  • Lots of follow up requirements will be required.

Further information

The Ear Foundation and Sense have produced 'Deafblindness and cochlear implantation: a practical resource', a booklet about cochlear implants for parents and carers of congenitally deafblind children. It can be ordered free of charge from our publications page. Due to the costs involved we would be grateful if copies were only requested by members of the specific targeted audience.
 

First published: Friday 28 March 2014
Updated: Tuesday 22 November 2016