How Cochlear Implants Work

The Children’s Hearing Center provides cochlear implants for children whose hearing loss is so severe that a hearing aid is of little or no benefit.

A cochlear implant is made of:

1. An external device
   • A sound processor contains a microphone that detects the sounds in the environment. Sounds are digitized by the sound processor. Small sound processing units can be worn behind the ear, or modular options are available and can be clipped on to your child’s clothing.
   • A magnetic headpiece sends the digital signals from the sound processor through the skin to the implanted device.
2. An implanted device
   • An internal device is placed under the skin, behind the ear. 
   • An electrode array is connected to the internal device. The array is a bundle of tiny wires that have electrodes that spread out along the length of the array. The array is inserted into the auditory portion of the inner ear (cochlea). The electrodes send electrical signals from the internal device to different areas of the cochlea to represent different sound frequencies.

Your child’s ability to understand what is happening in his/her environment improves when more detailed information reaches the brain. State-of-the-art cochlear implant devices have multiple electrodes which stimulate the auditory nerve fibers. This transmits more detailed information to the auditory center in the brain.