Your sense of movement and balance is based on your body's vestibular system, which keeps track of ...
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Your sense of movement and balance is based on your body's vestibular system, which keeps track of the motion and position of your head. Vision contributes some of this information, but most is based on structures called labyrinths in the inner ear on both sides of your head. When you move forward and back, or from side to side, or speed up or slow down, fluid inside canals in the labyrinth changes position. There are three canals, oriented differently, to sense movements in three dimensions, such as: turning around in circles, nodding, or doing a cartwheel. At the base of each canal is a small swelling with hairs projecting up. When the fluid moves, the hairs move, and nerve signals are sent to the brain. Motion sickness occurs when there is a disagreement between what you visually perceive as movement, and what is perceived by your body's vestibular system.