title: Inappropriate constancy scaling theory and the Mueller-Lyer illusion.
abstract: Gregory's Inappropriate Constancy Scaling explanation for visual illusion was investigated. If perceptual experience with real-life edges and angles, near and far, leads to constancy scaling which is inappropriately applied to the Mueller-Lyer configuration, then configurations which are based upon angles of regard in between the two extreme field patterns would produce illusory effects between the two conventional Mueller-Lyer effects. A model representing one edge of a cubic figure, i.e., one vertical and four horizontal lines, was constructed of wooden dowel rods and photographed at predetermined angles. Transparencies based on the photographed images were then used to determine the PSE at each of these angles. Generally, we interpret out results as supportive of the theory, since PSEs increase as a function of angular change from 0 degrees to 180 degrees. The linear trend is complicated by an unexpected cubic trend, but an explanation is proposed.
mesh_terms: D000293:Adolescent; D000328:Adult; D004193:Discrimination Learning; D005260:Female; D005556:Form Perception; D006801:Humans; D007088:Illusions; D008297:Male; D009903:Optical Illusions; D009949:Orientation