The auditory and vestibular systems often are considered together because their end organs share space within the petrous portion of the temporal bone (Fig. 16.1) and both arise from the otic vesicle. They also share the VIIIth cranial nerve, albeit the two almost completely separate divisions, auditory and vestibular classified as special somatic afferent. However, the auditory system is exteroceptive, whose purpose is to transduce airborne waves in the acoustic spectrum and most importantly deliver signals to higher centers of the auditory system for perception of sounds. The vestibular system in contrast is proprioceptive. Its receptors monitor head position and movement and convey this information into the brain stem, where it is integrated into the motor systems. The vestibular system is important for maintaining equilibrium and upright posture and for control of synergistic eye movements.