A cochlear implant is one of the only ways for people with severe to profound sensorineural hearing loss to hear.

You can think of the audio processor and the coil like little robots sending a message (like when your friends write an email), and think of the implant as being the robot who gets the message and sends it to the brain.

The audio processor takes these sounds and puts them into a code, or a special pattern of electrical pulses.

The audio processor and the coil are connected to each other with a small cable. The coil sends sound information through the skin to the implant. Of course, the person wearing it does not feel a thing! The coil contains a tiny magnet, just like the implant, and this magnetic force is what keeps the coil stuck in place on the head. People who have a CI can just cover up the coil and audio processor with hair and forget about it all day.

The implant holds all the high-tech electronics and a magnet, too. A doctor places the implant under the skin behind the ear. The doctor will do this during a small surgery while the person is asleep so that it does not hurt at all.

The wires attached to the implant are called electrode arrays. They contain electrical wires and contact points called electrodes. In the cochlea, the electrodes start up when they receive the electrical pulses from the implant. The hearing nerve picks up their signals and sends them on to the brain.

To summarise, a CI system takes the everyday sounds people hear and codes them into little electrical impulses which the brain understands as sounds. This only takes a few milliseconds, just like in normal hearing.