Bisecting the Ponzo illusion.
A modification of the Ponzo illusion, in which the judged lines are centered in different sized obliques, was presented to matched normal and mentally retarded males (ns = 8) under conditions of equal and unequal retinal sizes. Magnitude of illusion was affected by IQ (WISC) and by physical proximity rather than retinal contour. The results seem to imply a central rather than peripheral explanation for the illusion.
D000293:Adolescent; D006801:Humans; D007088:Illusions; D008607:Intellectual Disability; D007360:Intelligence; D008297:Male; D009903:Optical Illusions; D014796:Visual Perception