Cochlear amplifier

Cochlear amplifier is a technical term for the mechanical reinforcement of the traveling wave in the cochlea (Latin cochlea) in the inner ear of mammals.

In the cochlea, sounds and language are similar to a Fourier analysis broken down into its individual frequencies. It is up to a thousand -fold amplification of the traveling wave by the extremely rapid movement of the outer hair cells occurs ( hair cells in the organ of Corti ), the per second move up to twenty thousand (20,000 Hz). An outer hair cell is therefore also referred to as a motor cell. The motor cells have special motor proteins (special proteins ) to be able to move. The motor proteins called Prestin (from Italian presto "quick" ).

This cochlear amplifier causes a dynamic adaptation, so that even very quiet sounds can be perceived. The gain is not linear - noise with low sound pressure are higher reinforcements as noise with high SPL. The failure of the cochlear amplifier leads to deafness.