Your ears convert external sound waves into electrical impulses that are passed to the brain, where they are translated into what you perceive as sound. The inner ear (or labyrinth), which consists of the cochlea, vestibule and semicircular canals, is the region of the ear responsible for generating the electrical impulses that are sent to the brain.
Cochlea
The cochlea is a snail-shaped (coiled) tube that changes mechanical vibrations (sound waves) into electrical signals through a process called transduction. When an external sound is passed along the middle ear bones to the cochlea, the fluid within this part of the inner ear begins to vibrate. This vibration causes the tiny hair cells on the cochlea to move, generating an electrical impulse. The electrical impulse is then sent to the brain by the auditory (hearing) nerve, explains health educators at the Washington University School of Medicine in St. Louis, Missouri.
Vestibule
The vestibule is the part of the inner ear that connects the cochlea to the semicircular canals. This tiny structure contains the utricle and saccule, which are crucial in ensuring that your head and body maintain normal balance and positioning as you move about. Information gathered by the vestibule regarding the position of your body in space is passed to and analyzed by the brain. If the brain receives abnormal signals from the vestibule, these abnormal signals cause your body to readjust your head, body or eyes to counteract any type of body imbalance.
Semicircular Canals
The vestibule and the three fluid-filled semicircular canals within the inner ear work together to help the body remain balanced when you move, walk or run. When your body moves, the fluid within your semicircular canals also shifts. This fluid movement stimulates the tiny hair cells at the base of each semicircular canal. The stimulated hair cells generate an electrical impulse, which contains information on how the body is balanced, that is sent to the brain for interpretation.
