Definition of cocaine. : a bitter crystalline alkaloid C17H21NO4 obtained from coca leaves that is used especially in the form of its hydrochloride medically as a topical anesthetic and illicitly for its euphoric effects and that may result in a compulsive psychological need.
The inner hair cells transform the sound vibrations in the fluids of the cochlea into electrical signals that are then relayed via the auditory nerve to the auditory brainstem and to the auditory cortex.
It is a nerve in the head that transmits electrochemical signals that are transduced inside the cochlea of the inner ear and carrying them to the brain stem. This cranial nerve is the auditory component of the vestibule-cochlear nerve.