title: Decrement and the illusions of the Mueller-Lyer figure.
abstract: Decrement, a time-related decrease in the magnitude of the Mueller-Lyer illusion, was measured separately for the wings-out and the wings-in variants of the Mueller-Lyer figure. There were significant reductions of wings-out illusion magnitude during the decrement period. Observers viewing the wings-in segment showed a non-significant decrement pattern. Analyses of individual decrement patterns showed that illusion magnitude did not decrease for a number of observers even when there were significant time-related trends at the group level. Data for 80 observers imply that the mechanisms of perceptual learning proposed by previous models of Mueller-Lyer illusion decrement are not sufficient explanations of the decrement process.
authors.affiliation: Department of Psychology, University of Victoria, B.C., Canada.
authors.forename: C
authors.initials: C
authors.lastname: Porac
mesh_terms: D000328:Adult; D001288:Attention; D004193:Discrimination Learning; D005260:Female; D006185:Habituation, Psychophysiologic; D006801:Humans; D008297:Male; D009903:Optical Illusions; D009949:Orientation; D010364:Pattern Recognition, Visual; D011601:Psychophysics; D011930:Reaction Time; D012858:Size Perception