"We humans are wet, salty beasts."A typical cochlear implant consists of four key parts: A microphone attached to the ear, a speech processor worn behind the ear, a transmitter that provides electrical stimulation, and a surgically implanted array of electrodes, attached to the auditory nerve. The electrodes take the place of damaged cilia, which are tiny hairs inside the cochlea that vibrate in response to sound waves. These vibrating structures would normally trigger a response in the auditory nerve. Artificial electrical impulses can only do so much, which is one reason implants are limited to a few channels, Bendett said.