What is the function of the inner ear?

• A. Converts sound vibrations into neural signals
• B. Amplifies sound vibrations
• C. Filters frequencies
• D. Produces ear wax

Answer: (A)

The main job of the inner ear is to convert mechanical energy from sound into neural signals. In the cochlea, sound vibrations set the fluid inside in motion. Hair cells along the basilar membrane bend as a result, and their movement changes their electrical state, releasing neurotransmitters that trigger neural impulses in the auditory nerve. These impulses travel to the brain, where we perceive sound. The cochlea also maps different frequencies along its length, so frequency information is encoded as a spatial pattern. While outer hair cells help amplify and sharpen the response, the essential function of the inner ear is transduction—turning physical vibrations into neural code. Ear wax is produced in the outer ear canal, not the inner ear. Filtering of frequencies is part of what the cochlea does during transduction, but the key function to emphasize is conversion to neural signals.