The mammalian cochlea is an intricately designed organ that is exquisitely sensitive to sound. It possesses unique physical and chemical properties that permit this organ to function properly. This chapter describes some of the features of the cochlea including the cells that line the fluid filled spaces of the cochlear duct and the chemical composition of the fluids that allow the tissues to produce resting and acting potentials that assist in the transduction of acoustic stimuli into electrical signals to the brain. The structure of key structures in the cochlea are illustrated with light microscopy and ultrastructural images, including transmission and scanning electron microscopy. The unusual structural and functional features of these cells allow them to function in an orderly and precise fashion to shape the special sensory function of hearing in the normal cochlea of mammals.
KeywordsCochlea Stria vascularis Hair cells Spiral ligament Spiral ganglion neurons Organ of corti Transduction Tectorial membrane Basilar membrane Perilymph Endolymph
Dr. Rybak was supported by NIH grant DC02396 from NIDCD.
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