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PSL440Y1 Chapter Notes - Chapter 11: Streptomycin, Vestibulocochlear Nerve, Proprioception

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erincheetah56
8 Jun 2012
School
UTSG
Department
Physiology
Course
PSL440Y1
Professor
A

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Document Summary

The vestibular system monitors the position and movement of the head, gives us a sense of balance and equilibrium, and helps coordinate movements of the head and eyes. The vestibular and auditory systems both use hair cells to transduce movements. In mammals, all hair cells are contained within sets of interconnected chambers called the vestibular labyrinth (see fig. 11. 28) which include two types of structures with different structures: Otolith organs detects force of gravity and tilts of the head: contain the saccule and the utricle, located near the center of the labyrinth. Semicircular canals sensitive to head rotation: three arcing structures, lie in approximately orthogonal planes. Ultimately, these structures transmit mechanical energy, derived from head movement, to its hair cells. The saccule and utricle detect changes of head angle as well as linear acceleration of the head. Each otolith organ contains a sensory epithelium called a macula. Vertically oriented within the saccule and horizontally oriented within the utricle.

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