Cochlear implants and hearing aids can restore hearing in individuals affected with deafness. For ...

Hearing aids help the majority of people with mild-to-moderate hearing loss who have severe-to-profound sensorineural hearing loss ("nerve deafness") in both ears, even the most advanced and powerful aids may not adequately help. That's because hearing aids simply amplify sound and this amplified input can sound distorted. Despite being referred to as "nerve deafness," most sensorineural hearing loss is a result of damage to the inner ear (cochlea), not the hearing nerve.


A cochlear implant consists of an internal and external component. The internal component is surgically inserted under the skin behind the ear, and a narrow wire is threaded into the inner ear. The external component, which looks somewhat like a behind-the-ear hearing aid, is connected to the internal one through the skin via an external magnetic disk.

Incoming sounds are converted to electrical currents and directed to a number of contact points on the internal wire. This operation creates an electrical field which directly stimulates the auditory nerve, thus bypassing the defective inner ear. Unlike hearing aids, cochlear implants convert sound waves to electrical impulses and transmit them to the inner ear, providing people with the ability to hear sounds and potentially better understand speech without reading lips.