NROC64H3 Lecture Notes - Lecture 6: Semicircular Canals, Vestibular Nerve, Kinocilium
Document Summary
Contributes to sense of balance and spatial orientation. Also important for sensing body"s acceleration (part of any motion that involves a change in speed or direction: ex. acceleration in a car, ex. Acceleration around corner even at same speed, it is acceleration around corner. Semicircular canals: 3 hollow curved tubes in the skull, filled with endolymph (liquid in eardrum, responsible for signalling head rotation. Semicircular canals: ampulla: small chamber at base of each canal. Filled with endolymph: crista: contains hair cells with stereocilia enclosed within a gelatinous cap, cupula: gelatinous cap with nerve fibre attached to end. Otolith organs: consist of utricle and saccule. Responsible for signalling when the head is undergoing linear acceleration. Also responsible for signalling when head is being held in a tilted position. Otolith organs: each utricle and saccule contain macula, macula contains hair cells that are oriented to different directions, hair cells are embedded in gelatinous matrix, matrix topped by tiny crystals called otoliths.