Structural Elements in the Concept of Motion Sickness

Ashton Graybiel

Jan 1968 · Naval Aerospace Medical Institute, Naval Aerospace Medical Center

About this ebook

A slow rotation room in a laboratory environment provides an excellent instrument for the study of motion sickness because the experimenter can control not only the stressful Coriolis accelerations, but also other important procedural and environmental variables. By exploiting this control, combined with the judicious selection of experimental subjects, it was possible to confirm many previous findings and demonstrate that manifestations of disturbances in the vestibular system fall into two distinct categories. In the first category are reflex phenomena evoked by Coriolis accelerations when the head is rotated out of the plane of the room's rotation, and revealed through systems which, under natural stimulus conditions, have functional articulations with vestibular receiving areas. The symptomatology in the second category comprises an epiphenomenon superimposed on any manifestation of the first, when the unusual vestibular activity, presumably through facilitory-inhibitory processes, irradiates to cells or cell assemblies not normally stimulated. Selected experimental findings are used in defining the characteristics of manifestations in the two categories and in demonstrating the nature of the facultative linkage between the otherwise independent systems underlying manifestations in the two categories.