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What is a Cochlear Implant?

Cochlear Implants provide a sensation of hearing to people who have permanent, severe to profound deafness, and cannot hear the full range of speech sounds with standard hearing aids.

A young child with a Cochlear Implant fittedA Cochlear Implant is different from a hearing aid.

It has two parts: one is worn like a hearing aid, behind the ear or clipped on to clothing, and the other is surgically implanted.

A Cochlear Implant turns sound into electrical signals. Instead of simply making sounds louder, like a conventional hearing aid would, the Cochlear Implant provides a sensation of hearing by directly stimulating the auditory nerve using electrical signals.

Cochlear Implant deviceHow does a Cochlear Implant work?

To understand how a Cochlear Implant works, it is useful to know about how the ear works.

How a normally hearing ear works

With a Cochlear Implant, sound is picked up by the microphone worn on or near the ear on the external processor.

The sounds are then processed, changed into electrical signals and passed to a transmitter coil worn on the head and kept in place via a magnet.

The signals are sent by radio waves, through the skin to the implanted receiver and down the wire to the electrode in the cochlea. When the electrode receives the signal, it makes tiny currents that travel along the auditory nerve to provide a sensation of hearing.


In Oxford we use three manufacturers:

Following a thorough assessment, we will make a recommendation about which implant system is best for you based on a variety of factors.

Adults and children with Cochlear Implant systems from all three manufacturers do equally well.

There are differences in the way the implant systems process sound and deliver electrical signals to the cochlea. The external processors also look different and connect with different accessories.

We will explain the differences between the manufacturers and show you models of the systems during your assessment.

We can put you in contact with people who have cochlear implants to talk about their experiences.

Unless there is a medical or physical reason why one system is recommended, you can choose which system you would prefer.

Cochlear implant systems from each manufacturer are not interchangeable. Once you have an implant from one manufacturer, you will need to continue to use their sound processors.

Last reviewed:19 April 2022