Sensation of rotation about a vertical axis with a fixed visual field in different illuminations and in the dark

Abstract

This paper compares the motion sensations of a subject rotated about a vertical axis for two fixed visual fields (a large peripheral field and a single central spot) and in darkness. Motion sensation is described in terms of threshold, frequency response, and subjective displacement and velocity. The perception of angular acceleration showed significantly lower threshold and reduced latency time for the illuminated presentation. The level of illumination, however, produced no significant difference in threshold. The subjective frequency response, measured by a nulling method, showed a higher gain in the illuminated presentation, particularly at low frequencies and accelerations. With the subject rotating a pointer to maintain a fixed heading during triangular velocity stimuli, subjective displacements showed no difference for all different visual cues. Magnitude estimates of the after-rotation associated with deceleration from a constant velocity showed a quicker rising speed, larger subjective velocity and longer duration in the illuminated presentation. All the results suggest that the oculogyral illusion is principally responsible for producing a lower threshold in the illuminated presentation, although the fixed peripheral visual field tends to reduce reliance upon vestibular signals. At lower intensity rotation stimuli, this effect is especially apparent.

Self-motion sensation influenced by visual fixation

“…With higher accelerations, this effect becomes smaller and is nonsignificant at 12 deg/sec', Our interpretation of these data is that the oculogyral illusion led to an earlier "awareness of movement" at low accelerations, as in our experiments. Huang and Young (1981) did a more extensive study. Their experiments were performed in an aircraft trainer with velocities limited to 40 deg/sec and accelerations limited to 20 deg/see', A further difference between their study and ours is that they did not measure eye movements or require from the subject a distinction between object and self-motion.…”

“…The whole-field visual stimulus has the effect of shortening the duration of the motion sensation but has less effect on the perception of initial maximal ve-the oculogyral illusion and the sensation of selfmotion, as compared using the global statement "awareness of movement" (Huang & Young, 1981;Marshall, 1967), the above two reports and a further one from our laboratory (B. Waespe, W. Waespe, & Henn, 1980) actually agree that there are two opposing factors of how a visual stimulus influences motion detection: the oculogyral illusion can lead to an enhanced awareness of motion, especially at low accelerations, but the sensation of self-rotation is reduced, especially at high accelerations.…”

“…Correspondingly, the results of a study with human subjects, which explored subjective sensation during vestibular stimulation in darkness with a subject-stationary surround and using the same primate turntable, were compatible with predictions derived from animal experiments. Other studies, however, came to the conclusion that the presence of a subject-stationary visual object enhanced motion sensation instead of attenuating or shortening it (Huang & Young, 1981;Marshall, 1967). We therefore undertook the investigation described below.…”

Inertial acceleration as a measure of linear vection: An alternative to magnitude estimation

“…These measures include subjective estimates, postural adjustments, and judgments of heading or direction (Warren & Kurtz, 1992). Another measure, not often cited, is the extent to which a moving visual surround interferes with an observer's ability to "null" perturbations in his or her inertial self-motion (Huang & Young, 1981, 1987Zacharias & Young, 1981). The nulling paradigm is described below.…”

Perceived orientation, motion, and configuration of the body during viewing of an off-vertical, rotating surface

“…Extensive testing of convergence models of perceived body motion has been conducted using prolonged, constant-velocity rotation around the vertical z-axis of the body or about the vertical x-axis of the head (Bles & Kapteyn, 1977;Dichgans & Brandt, 1972;Grosser & Grosser-Cornehls, 1973;Huang & Young, 1981;Mergner et aI., 1983;Waespe, Waespe, & Henn, 1980;Young, Dichgans, Murphy, & Brandt, 1973).…”