Audiology and hearing aids.

Audiology is the study of hearing, balance, and related ear disorders. Hearing disorders may be the result of congenital abnormalities, trauma, infections, exposure to loud noise, some medications, and aging. Some of these disorders may be corrected by hearing aids and cochlear implants. Hearing aids amplify sounds so damaged ears can discern them. Some aids fit over the ear with the receiver behind the ear, and some fit partially or completely within the ear canal. Cochlear implants directly stimulate the auditory nerve, and the brain interprets the stimulation as sound.