Sense of balanceThe sense of balance or equilibrioception is the perception of balance and spatial orientation. It helps prevent humans and nonhuman animals from falling over when standing or moving. Equilibrioception is the result of a number of sensory systems working together; the eyes (visual system), the inner ears (vestibular system), and the body's sense of where it is in space (proprioception) ideally need to be intact. The vestibular system, the region of the inner ear where three semicircular canals converge, works with the visual system to keep objects in focus when the head is moving.
DysmetriaDysmetria (wrong length) is a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is a type of ataxia. It can also include an inability to judge distance or scale. Hypermetria and hypometria are, respectively, overshooting and undershooting the intended position. Dysmetria is often found in individuals with multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), and persons who have had tumors or strokes.
