HUBS1107 Lecture Notes - Lecture 6: Vestibular Duct, Central Nervous System, Cochlear Duct
26 Oct 2018
School
Department
Course
Professor
Document Summary
Another view of bony compartment where balance organs lie. Contains auditory receptors two membranes divide cochlea into three compartment. Reissner"s (also known as vestibular) membrane and basilar membrane three compartments/scala. Scala vestibuli, scala media (cochlear duct) & scala tympani compartments contain different fluids: Perilymph (similar to extracellular fluid) found in scala vestibuli and scala tympani. Endolymph (high k+) secreted by stria vascularis, found in cochlear duct. It drives the potassium into the hair cells, opening up the channels and forcing the potassium in to the hair cells - for action potential. Inner hair cells - single row - fine discrimination. Sends the information back to the central nervous system (cns) Outer hair cells - three rows - detection of sound. Fine tune the sound so improve ability of discriminating frequency of sound. They don"t send any information back to the brain. Hair cells contain stereocilia, which stick into tectorial membrane. Vibrations set up in compartments stimulate hair cells.
