A balance disorder is a disturbance that causes an individual to feel unsteady, for example when standing or walking. It may be accompanied by symptoms of being giddy, woozy, or have a sensation of movement, spinning, or floating. Balance is the result of several body systems working together. The eyes (visual system), ears (vestibular system) and the body’s sense of where it is in space (proprioception) need to be intact. The brain, which compiles this information, needs to be functioning effectively.
Source: http://en.wikipedia.org/wiki/Disability#Balance_disorder
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