In a cochlear implant, which component is implanted inside the cochlea to stimulate the auditory nerve?

• A. External sound processor
• B. Microphone
• C. Electrode array
• D. Receiver

Answer: (C)

The part implanted inside the cochlea that stimulates the auditory nerve is the electrode array. It is inserted into the cochlea during surgery and delivers electrical pulses to the nerve fibers, bypassing damaged hair cells and preserving the cochlea’s frequency layout by stimulating different regions along its length. The other components work outside or connect to this implanted piece: an external sound processor and microphone capture sound and send encoded signals to an implanted receiver/stimulator under the skin, which then powers the electrode array.