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.
The vestibulocochlear nerve carries information concerning balance from the inner ear to the brain. Damage to the vestibulocochlear nerve can cause changes in head and neck position, as the affected animal may feel a false sense of movement, or may be having problems with hearing.