Displacement effects caused by converging lines and dots.
Changes induced in orientation were examined under conditions of a dot or full-line version of a stimulus consisting of a test and inducing line. 44 subjects visually extended the test line to the surrounding circle on 11 trials and indicated their response by a mark on the circle. Magnitude of illusion was reduced by 54% for the dot version compared with the full-line form, but both produced an illusion significantly greater than zero. A significant practice effect was obtained with full lines but not with the dot form. Results are discussed in terms of lateral inhibition theory and related research.
Radenhausen
R A
RA
Northern Kentucky Comprehensive Care Center, Covington 41011.
Tatz
S
S
D001288:Attention; D005556:Form Perception; D006801:Humans; D007088:Illusions; D009903:Optical Illusions; D009949:Orientation; D010364:Pattern Recognition, Visual