The Physiology of the Vestibular Nuclei

Abstract

The experiments of Goltz (1870), Mach (1873), Breuer (1891), Ewald (1892), Barany (1907) and Steinhausen (1931, 1933) can be considered as a very important first step in the development of the physiology of the vestibular system. They established a theory of the mechanics of the peripheral vestibular sensory mechanisms which is still basically valid today. The various sensory cells in the peripheral vestibular sensory organ serve as receptors for linear and angular accelerations about different axes, thus providing a three dimensionally organized sensory system for orientation in space. Various other sensory systems such as the visual, somatosensory and acoustic apparatus combine with the vestibular organs in assuring a high sensitivity for the adjustment of the body in space. Part of this regulation is achieved by means of interaction in the vestibular nuclei which integrate the activity of the various vestibular receptors as well as the activity of other sensory structures which converge directly or indirectly on the vestibular neurones. As the vertebrates developed from lower to higher forms other sensory systems such as the somatosensory and visual systems became more and more important in the regulation of posture; however, the vestibular nuclei still remain an important integrative structure that deserves the interest of anatomists as well as physiologists.