Mechanical Factors in the Excitation of the Lateral Lines of Fishes

Abstract

The effective stimulus to a neuromast lying inside a typical lateral line system will be one that produces a movement of the cupula of the neuromast relative to the wall of the lateral line canal. The force moving the cupula must derive from liquid movement in the canal, and such motion arises from the net pressure gradient along the short stretch of canal carrying the neuromast. This gradient can be measured in terms of the local accelerations of the medium adjacent to the canal relative to the surface of the fish. If the medium adjacent to the lateral line moves in exactly the same way as the surface of the fish carrying the lateral line, the sense organs of the lateral line will not be stimulated (Denton and Gray 1983; see also Chap. 23.4).