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Abstract Balance system disorders are common worldwide. It estimated that 40% of the population in the United States experience some form of dizziness or balance disorder over the course of a lifetime. A study conducted in the United States using data from 2001-2004 National health and Nutrition Examination Surveys suggested that 35 % of adults showed some form of vestibular dysfunction (Argawal et al., 2009). The anatomical location of vestibular disorders that cause vertigo may be peripheral or central. The semicircular canals and the otolith are two anatomical locations where peripheral vestibular lesions can cause vertigo (Toshiaki Y., 2003). The otolith system detects linear acceleration, by which it senses head translation in three dimensions. The system also detects head tilts relative to the gravity vector that serves as an absolute reference in space. The maculae utriculus and sacculus are, however, unable to discriminate between translations and tilts because both actions stimulate the hair cells in a similar way. Many experiments have been performed and theories were designed to reveal how the brain deals with this ambiguity problem. This also complicates the design of otolith tests (Angelaki et al., 2005). |