Three-dimensional flows in the vicinity of the hair cells of the cochlea

The cochlea is the spiral-shaped part of the inner ear in which mechanical waves are transformed to neural output. It is the hair cells residing in the narrow gap between the tectorial membrane and organ of Corti that are considered to be the primary transducers of the hearing mechanism. For the first time, three-dimensional flow fields are obtained in the vicinity of the hair cells. The resulting flow fields are then incorporated into an existing numerical simulation.

Three-dimensional analysis of the gap flow induced by displacement of the tectorial membrane and organ of Corti yields results that differ qualitatively, but not quantitatively, from those of a two-dimensional analysis.

In addition to the flow induced by membrane displacements, the net flow through the gap, which is driven by pressures in scala vestibuli and the inner sulcus, is analyzed. Three-dimensional analysis indicates that the model may admit three modes of propagation.