Displacement of the semicircular canal cupula during sinusoidal rotation

We propose on the basis of these results that, during rotation, the cupula functionally behaves as a diaphragm with its greatest mechanical sensitivity adjacent to the crista. Hence, a minimal volume of the endolymph must be displaced to produce a given deflection of cilia. This diaphragm arrangement, along with the non-uniform thickness of the cupula and the profile of the endolymph flow through the canal, suggests a graded response along the length of the crista. The cupula may thus behave as a primary information filter which 'pre-processes' and separates rotational information (related to angular velocity and angular acceleration) through a 'vestibular place phenomenon'.