Purchase this article with an account.
Gideon P. Caplovitz, Peter U. Tse; Aperture induced motion: Illusory motion percepts arising from conflicting terminator and component motion signals. Journal of Vision 2007;7(9):978. doi: 10.1167/7.9.978.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
When a drifting grating is observed through a stationary circular aperture, the aperture itself will appear to either displace (De Valois & De Valois, 1991) or move (Zhang, Yeh & De Valois 1993; Tse & Hsieh 2006) creating an illusory global motion percept. Here we describe a novel stimulus in which a drifting grating moving behind a stationary rectangular aperture induces an illusory motion percept: Aperture Induced Motion (AIM) that is dependent upon the relationship between terminator and component motion. The stimulus is a variant of that used to demonstrate the Barberpole Illusion (Wallach 1935). When a drifting grating is viewed through a stationary and diagonally-oriented rectangular aperture, either the aperture or the occluders can be observed to move. In a series of motion-nulling and constant-stimuli psychophysics experiments we describe the relationship between the illusory percept and the orientations of the aperture and drifting grating and explore the roles of occlusion, component-motion, trackable features, and contour relationships. Results: The angle between the orientation of the grating, which determines the component motion, and the orientation of the aperture, which determines the terminator motion, is critical in determining the magnitude of the AIM.
This PDF is available to Subscribers Only