A cochlear implant is a small electronic device that partially restores hearing. It can help to provide a sense of hearing to people who have severe to profound hearing loss from inner-ear damage and no longer helped by using hearing aids. Unlike hearing aids, which amplify sound, a cochlear implant bypasses damaged portions of the ear to present acoustical signals to the auditory nerve. Hearing through a cochlear implant is different from normal hearing and takes time to learn. However, it allows many hearing-impaired patients to understand speech in person or over the telephone, or recognize alarming signals.