Observations of the Organ of Corti Under in Vivo-Like Conditions

Abstract

The organ of Corti of the rat has been investigated within minutes after death in different fluids bathing the organ of Corti. Static compliance of the tectorial membrane across the membrane was measured by mi-crosprings, and the response of the membrane to a vibrating micro-electrode was studied. In addition, fluid motion about the organ caused by the placement of a vibrating micro-electrode on the tectorial membrane was observed. The static compliance of the tectorial membrane was unaffected by the bathing solutions. Dynamic characteristics of the membrane could be completed altered by the addition of aldehyde solutions. As the cochleas used by von Békésy (1960) were preserved in formaldehyde solutions, it is concluded that his observations regarding the dynamic characteristics of the tectorial membrane were in part artifact. It is suggested that a proper description of the mechanics of the organ of Corti must include a tectorial membrane whose limbal attachment allows for both rotation and displacement. Such a description is presented. A streaming of fluid was observed directed from Hensen's cells toward the cochlea wall. Possible mechanisms for the generation of this streaming are discussed.