A cochlear implant is an electronic device in which an extracorporeal speech processor converts sound into a certain coded form of electrical signal and restores or reconstructs the hearing function of a deaf person by directly exciting the auditory nerve through an electrode system implanted in the body. In recent years, with the development of electronics, computer technology, phonetics, electrophysiology, materials science, and ear microsurgery, cochlear implants have moved from experimental research to clinical application. Cochlear implants are now used worldwide as a routine treatment for severe to total deafness. The cochlear implant consists of a cochlear implant electrode, a speech processor, a microphone and a transmission device, except for the cochlear implant electrode, which is implanted in the human body (cochlear shaft), and the rest of the cochlear implant, which is magnetically attached to the head (the implant is attached to the body through the skull).