A cochlear implant is an electronic device that partially restores hearing in people who have severe hearing loss due to damage of the inner ear and who receive limited benefit from hearing aids. The system is comprised of two central pieces: a processor that fits behind the ear and an internal piece implanted under the skin.
The processor captures and processes sound signals, which are transmitted to the receiver implanted behind the ear. The receiver sends the signals to electrodes sitting in the snail-shaped inner ear (cochlea). These signals are then received by the auditory nerve and directed to the brain.
The brain interprets those signals as sounds, though these sounds won't be just like normal hearing. It takes time and training to learn to interpret the signals received from a cochlear implant, though after a year of use most implant patients make considerable gains in speech understanding.
Although results vary from person to person, most find that cochlear implants help them communicate better and improve their quality of life. They report improved:
- Ability to hear speech without needing visual cues
- Recognition of normal, everyday environmental sounds
- Speech reading
- Ability to hear soft sounds
- Ability to find where sounds are coming from
March 19, 2015
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