Functions of separate sensory receptors of nonauditory labyrinth of the cat

Abstract

A technique for plugging individual semicircular canals of cats was developed, and it was established that the plugging of a semicircular canal completely blocked its receptivity without influencing the functions of the other vestibular receptors. It was found that cats with all six semicircular canals plugged were lacking all sensitivity to angular acceleration, but they retained normal responses to linear acceleration. Results of several vestibular tests led to the conclusion that the vertical semicircular canals initiate corrections for fast angular displacements from the normal orientation when the displacements are about horizontal axes and that the otoliths initiate corrections for slow angular displacements about horizontal axes. In tests of single horizontal canals, the durations of postrotatory nystagmus were the same after rotations in opposite directions. It was concluded that in the intact animal both horizontal semicircular canals contribute equally to reception of angular acceleration in both directions.