The vestibular system functions to give you a sense of which way your head is pointing in relation to gravity. It enables you to discern whether your head is upright or not, as well as helping you to maintain eye contact with stationary objects while your head is turning. Also located within the inner ear, but less to do with sound and more
concerned with the movement of your head, are the semicircular canals.
Again filled with fluid, these looping ducts act like internal accelerometers that can detect acceleration (ie, movement of your head) in three different directions due to the positioning of the loops along different planes. Like the organ of Corti, the semicircular canals employ tiny hair cells to sense movement. The canals are connected to the auditory nerve at the back of the brain.
Your sense of balance is so complex that the area of your brain that’s dedicated to this one role involves the same number of cells as the rest of your brain cells put together.