The functioning of the vestibular system depends on information from many systems, hearing as well as vision and muscle feedback.

The vestibular system consists of three semicircular canals , the utricle , and the saccule . Each of the semicircular canals lies anatomically in a different plane, each plane at a right angle to each other. Thus, each deals with different movement: up and down, side to side, and tilting from one side to the other. All contain sensory hair cells that are activated by movement of inner ear fluid (endolymph). As the head moves, hair cells in the semicircular canals send nerve impulses to the brain by way of the vestibular portion of the acoustic nerve (VIII cranial nerve). These nerve impulses are processed in the stem of the brain and in the brain's cerebellum.

The ends of the semicircular canals connect with the utricle, and the utricle connects with the saccule. While the semicircular canals provide information about movement of the head, the sensory hair cells of the utricle and saccule provide information to the brain (again through the vestibular portion of the acoustic nerve) about head position when it is not moving.