Induced Roll Vection from Stimulation of the Central Visual Field

An important consideration for some types of flight simulation is that sufficient visual information be provided for a perception of self-motion. A general conclusion of earlier research is that peripheral stimulation (outside a 30 deg. diameter area of the central visual field) is necessary for perceived self-motion to occur. More recently Andersen and Braunstein (1985) demonstrated that induced self-motion could occur when visual information simulating forward motion of the observer was presented to a limited area of the central visual field. In the present study, the perception of induced roll vection (rotation about the line of sight) from visual stimulation of the central visual field was examined. Subjects viewed computer generated displays that simulated observer motion relative to a volume of randomly positioned points. Two variables were examined: 1) the presence or absence of a simulated forward motion, and 2) the presence of a 15 deg. or 30 deg. sinusoidal roll motion. It was found that: 1) induced roll vection occurred with stimulation restricted to a 10 deg. diameter area of the central visual field; 2) greater postural instability occurred for displays with a 30 deg. roll as compared to a 15 deg. roll; and 3) significantly greater postural instability occurred along the X-axis (left/right) as compared to the Y-axis (front/back). The implications of this research for flight simulation will be discussed.