Hearing loss is often caused by problems in the cochlea, snail-shaped tubes inside the inner ears. Unlike a traditional hearing aid, which amplifies sound, a cochlear implant bypasses the portion of the inner ear that is damaged and stimulates the auditory nerve directly with electric pulses. The pulses travel on to the brain, which interprets them as sound.
A cochlear implant has two parts. The internal part is placed during a short, outpatient surgery. The external part is activated a few weeks later and fine-tuned over the following months.