ABSTRACT
The inner ear is a transducer of mechanical force to an appropriate neural excitation. The key element is the receptor cell, or hair cell, which has stereocilia on the apical surface and afferent neural synapses on the lateral walls and base. Almost every component of the cochlear cross section has been proposed at one time or another as the fundamental resonance element. Consequently, there are three mechanical devices in the inner ear of vertebrates that provide perception in the different frequency ranges. At zero frequency, that is, linear acceleration, the otolithic membrane provides a constant force acting on the stereocilia of hair cells. The stereocilia of the inner hair cells are not attached to the overlying tectorial membrane, so the motion of the fluid in the inner sulcus must provide the mechanical input to these primary receptor cells.
