PHTY209 Lecture Notes - Lecture 9: Vestibular Nerve, Vestibular Nuclei, Otolith
Document Summary
Lecture 1: special senses vestibular: des(cid:272)(cid:396)i(cid:271)e the st(cid:396)u(cid:272)tu(cid:396)e a(cid:374)d fu(cid:374)(cid:272)tio(cid:374) of the i(cid:374)te(cid:396)(cid:374)al ea(cid:396), i(cid:374)(cid:272)ludi(cid:374)g the (cid:396)ole i(cid:374) postu(cid:396)al a(cid:374)d o(cid:272)ula(cid:396) stability structure. Also called the labyrinth and contains 2 main structures- the cochlear and the vestibular system. Vestibular information is essential for postural control and for the control of eye movements. Vestibular apparatus contains sensory receptors that respond to the position of the head relative to gravity and to head movements. Information is converted into neural signals that are conveyed by the vestibular nerve to the vestibular nuclei. Both are called otolithic organs; membranous sacs within the vestibule. Respond to head position relative to gravity & to linear acceleration and deceleration. Inside each utricle & saccule is a sensory receptor called the macula. Macula consists of hair cells embedded in a gelatinous material. On top of gelatinous material are otoconia (calcium carbonate crystals) Hair cells synapse with neurons of vestibular nerve (branch of cn 8)
