Influence of parallel and orthogonal real lines on illusory contour perception.
Real lines and illusory contours (ICs) have been reported to either interfere with or facilitate the perception of the other, depending on real line orientation and contrast. Here we investigate contextual effects of real lines on illusory contour perception. Curvature discrimination thresholds of Kanizsa-contours were measured for superimposed real lines of different sub- and suprathreshold contrasts. We find that parallel lines interfere with curvature discrimination at suprathreshold, whereas orthogonal lines interfere at subthreshold contrasts. We did not find stable facilitating effects of lines in any orientation or contrast. These results are discussed in relation to existing physiological and imaging data.
Institute of Imaging Science, Department of Psychology, Vanderbilt University, Medical Center North, 1161 21st Ave. S., Nashville, TN 37232-2310, USA. barbara.dillenburger@vanderbilt.edu
Barbara
B
Dillenburger
Anna W
AW
Roe
D000328:Adult; D005260:Female; D006801:Humans; D007088:Illusions; D010775:Photic Stimulation; D011601:Psychophysics; D017603:Signal Detection, Psychological; D014796:Visual Perception; D055815:Young Adult