Rotational coding by semicircular canals
Rotational movement of the head is encoded by the hair cells in the base of the semicircular canals. As one of the canals moves in an arc with the head, the internal fluid moves in the opposite direction, causing the cupula and stereocilia to bend. The movement of two canals within a plane results in information about the direction in which the head is moving, and activation of all six canals can give a very precise indication of head movement in three dimensions.
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"OpenStax College, Sensory Perception. December 8, 2013."
http://cnx.org/content/m46577/latest/
OpenStax CNX
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