HSC 350 Study Guide - Midterm Guide: Semicircular Canals, Posterior Grey Column, Ventral Cochlear Nucleus
21 Mar 2017
School
Department
Course
Professor
Document Summary
1: the organ of corti, sits on the basilar membrane and contains the auditory receptor cells. 100 fold: descending efferent input from the brain can regulate outer hair cell shape and effect inner hair cell response and auditory sensitivity. Intense sound basilar membrane vibrates with greater amplitude -> increased hair cell activation -> nerve fibers fire aps at greater rates. The vestibular system: perception of self-motion, head position, and spatial orientation relative to gravity; stabilizes gaze, head and posture. The vestibulo-ocular reflex circuit: mechanism for producing eye movements that counter head movements, permitting gaze to remain fixed on a particular point, excitatory input from horizontal canal on one side produces eye movements toward opposite side. Positional alcohol nystagmus: semicircular canals selectively transduce angular velocity and acceleration under normal circumstances are insensitive to gravitational orientation and linear acceleration. In pan 2, nystagmus beats to the uppermost ear usually associated with motion sickness; major contribution to the hangover.
