Reversed rotary motion perception

• Published in: Journal of the Optical Society of America. A, Optics and image science Vol. 8; no. 9; p. 1510
• Main Authors: Werkhoven, P, Koenderink, J J
• Format: Journal Article
• Language: English
• Published: United States 01-09-1991
• Subjects: Humans; Mathematics; Motion Perception - physiology; Rotation
• ISSN: 0740-3232
• DOI: 10.1364/JOSAA.8.001510

A stroboscopically presented revolving annulus composed of dots is used to elicit rotary motion perception. Observers judge the direction of rotary motion. We find sharp and gradual transitions in the probability for reversed motion perception as a function of the angle of rotation between successive frames. These transitions reveal that matches between nonsuccessive frames can dominate motion perception. The transitions are scale invariant. The strength of a match is discussed in terms of a motion strength function, which is a separable function of the angle of rotation between successive frames and the frame repetition rate. The dependence of motion strength on the frame repetition rate (time function) is computed from the transitions. The similarity of this time function for rotary motion with the time function for linear motion [Psychol. Rev. 88, 171 (1981)] suggests that mechanisms for the discrimination of rotary motion address local detectors of linear motion.