Counterrolling of the eyes and its dependence on the magnitude of gravitational or inertial force acting laterally on the body

Counterrolling of the eyes was measured in five healthy persons when inclined on a tilt-chair and when exposed to a change in direction of force on a human centrifuge. For equivalent changes in direction of force incident to the subject, the magnitude of the force was greater on the centrifuge. When the amount of roll was plotted as a function of the incident angle of force, divergent curves were obtained for tilt-chair and centrifuge data. When the amount of roll was plotted as a function of magnitude of laterally-acting force as the independent variable, a single curve resulted indicating a straight line relation within the range of 1 g . These findings not only constitute definitive proof that the counterrolling reflex can be released by gravitational (and inertial) force but also are consistent with the current theory of the functioning of the otolith organs. Submitted on January 20, 1959