A cochlear implant is a surgically implanted device that bypasses damaged hair cells in the ear and provides electrical stimulation directly to the auditory nerve, giving patients who are severely hearing impaired or profoundly deaf the ability to hear. It is most beneficial for those who cannot be helped with a traditional hearing aid.
A cochlear implant works differently than a hearing aid. Hearing aids amplify sounds so that a person with nerve damage can hear more clearly. Cochlear implants generate an electrical signal that the brain interprets as sound. The implant has an external portion that sits behind the ear, consisting of a microphone, a speech processor and a transmitter. These work in tandem with the internal components, a receiver and array of electrodes, which have been implanted in the ear. The microphone picks up sound and sends it to the speech processor, which converts these signals to digital impulses and sends them to the transmitter. The transmitter, in turn, sends the processed audio signals to the receiver. From there, they are transmitted directly to the brain through the auditory nerve. While a cochlear implant does not cure deafness or restore hearing loss, it does allow a patient to perceive sound, and can help him or her to converse again.
Those experiencing severe to profound sensorineural hearing loss (the result of nerve damage to the inner ear) who can’t benefit from conventional hearing aids are prime candidates for cochlear implants. These implants are most helpful in patients with solid language and communication skills and a hearing loss that occurred later in life. Younger children (typically between the ages of two and six) also benefit, since a cochlear implant exposes them to sounds during their formative learning years, while they are developing speech and language skills. Post-implantation therapy is a crucial component in the success of cochlear implants; learning to use them correctly takes time and effort.