Cochlear Implants

A cochlear implant, also known as  “the bionic ear,” is an electronic device that helps treat people suffering from sensorineural hearing loss (hearing loss caused by damage to the inner ear or nerve pathways). Part of the device is surgically implanted behind the skin in the head, while the other parts are located externally behind the ear. The implant offers an alternative for those who receive little benefit from hearing aids. Unlike a hearing aid, a cochlear implant does not amplify or clarify sound. It works by picking up sound, bypassing damaged portions of the auditory system, and electronically stimulating the hearing nerves. These nerves then send signals to the brain, which interprets them into recognizable sounds. 

Cochlear implantation, approved by the FDA in 1984, is a relatively new treatment, and research is still being conducted about its effects. Not everyone receives the same benefits from the procedure, and sometimes intensive post implantation therapy is needed, especially with children. The procedure also is expensive.  The total cost of the evaluation, surgery, device and rehabilitation is around $40,000, though many insurance companies will cover the cost. Still, more than 100,000 people worldwide have received the operation, and it remains the only treatment for sensorineural hearing loss. 

A cochlear implant cannot cure or restore hearing, but it does give the perception of sound to people suffering from both acquired and congenital hearing loss. People with acquired hearing loss who receive the implant learn to associate the electronic signals with the sounds they remember. People who were born with hearing loss must learn what these new sounds are. 


The cochlear implant consists of five parts, three external and two internal:


  • Microphone- Sitting behind the ear, it looks like a hearing aid. It picks up sound and sends it to the speech processor.
  • Speech processor- A small computer that analyzes and arranges the sounds and sends them to the transmitter. Can be worn behind ear or in breast pocket.
  • Transmitter- Converts sound signals into electric impulses and sends them to the implanted receiver. Sits just above the ear. 


  • Receiver- Receives electric impulses and delivers them to the implanted electrodes in the cochlea. Placed just under the skin above the ear. 
  • Electrodes- Collects the impulses and sends them to the auditory nerves, which then send signals to the brain. The electrodes are located in the cochlea. 

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