Auditory brainstem response
Auditory brainstem response is an important test of inner ear function. This allows measurement of the time it takes a sound in a headphone worn by the patient to become a nerve impulse traveling up the vestibulocochlear nerve. A delay in the time for this event indicates that there is pressure on the cochlear nerve, which could indicate a benign tumor on the coverings of the vestibulocochlear nerve called an acoustic neuroma.
Learn more at the New York Head and Neck Institute.