What Is A Cochlear Implant?

Are you considering a cochlear implant? The advantages of an implant-- participating in conversations without lip reading, for example-- make them a popular choice. But what exactly is a cochlear implant?

How does hearing work?

To understand what a cochlear implant does, it's useful to first have an understanding of how hearing works. In a healthy ear, sound enters the ear canal where it encounters the eardrum. The eardrum converts the sound into electric impulses, which are sent via three small bones to the cochlea. The cochlea is a tube consisting of two types of sensory cells. Outer hair cells act as an equalizer--they increase the volume of quiet sounds, and lower the volume on sounds that are loud. Inner hair cells send the electrical impulses to the auditory nerve.

The auditory nerve sends the information it receives to the brain, which then processes and makes sense of it.

What is a cochlear implant?

Cochlear implants give those who are severely hearing-impaired the ability to hear sound. The implant is actually divided into two parts. One part picks up surrounding noises using a microphone. Those sounds then travel to a speech processor, which converts the sound waves into electrical impulses. The electrical impulses are sent via a transmitter to the second part of the cochlear implant-- a group of electrodes placed inside the ear, by the auditory nerve.

The electrodes distribute the electrical impulses to the auditory nerve. Essentially, a cochlear implant simply bypasses the eardrum and cochlea.

How is a cochlear implant installed?

When having a cochlear implant installed, you will first undergo surgery to have the electrodes placed inside the ear, near the cochlea. This surgery is generally an outpatient procedure. Once your doctor has determined that enough healing has occurred--generally one or two weeks after the procedure--they will fit you with the second part of the implant on the outside of your ear.

What should you expect from a cochlear implant?

Once the device is fully installed, you will notice many new sounds. Many people find that cochlear implants allow them to hear speech during conversations, talk on the phone, listen to music, and even hear their own voice. Cochlear implants don't completely replicate normal hearing, but they do allow you to have an increased awareness of the sounds around you.

Talk with your doctor or audiologist to see if a cochlear implant is right for you.