Cochlear implants are used on children and adults who have minor to severe hearing loss. The implants are considered to be more effective than hearing aids and are a long-term solution for hearing loss. While hearing aids help to make sounds louder, cochlear implants carry sound signals from the cochlea (the auditory portion of the ear) to the brain through the auditory nerve, responsible of carrying auditory information from the cochlea to the brain. Although the hearing is not restored for the patient, the cochlear implant is useful for stimulating the auditory nerve directly, which helps to mimic the sensation of sound. Two main components are used with cochlear implants, which includes an internal part that is surgically implanted into the ear and an external part that hooks over the ear.
The internal part of the cochlear implant, the receiver-stimulator, is surgically placed on the temporal bone, located at the lower sides of the skull, underneath the skin with a small incision that is made by a surgeon. The transmitter sends the different signals to the internal part of the implant to convert them into pulses. The pulses are sent to the electrodes, which work to stimulate the auditory nerve, which begins to interpret it as sound from a part of the brain. Inserting the receiver-stimulator takes an average of one to two hours to perform before you're able to head home. The external part of cochlear implants, the speech processor, contains a microphone and a transmitter in a small unit. The speech processor is fitted two weeks after the receiver-stimulator is surgically inserted behind the ear. The signals are analyzed and digitized by the processor before they're sent to the transmitter. The transmitter is used to send different codes to the implanted receiver through the magnetic coupling that is in place. The external component of the implant is connected to the speech processor and the microphone with a wire that is used.