The role of memory in perceiving subjective contours

Abstract

In the variety of subjective contours that are structured like Kanizsa's triangle, shapes consist partly of edges of elements that make up the patterns that give rise to the subjective contours and partly of the subjective contours. It was found that familiarity with the shape that fit the subjective-contour-inducing pattern in this fashion increased the likelihood that subjective contours were perceived when the "containing" pattern was shown. Six containing patterns were constructed that did not readily yield subjective contours when the fitting shapes were not familiar. It was found that these containing patterns yielded subjective contours considerably more often when their fitting shapes had been made familiar than when they had not been. This result was obtained even though all subjects were acquainted with subjective contours before the containing patterns were shown, and even though they were asked whether or not they saw subjective contours when they saw the containing patterns. In a second experiment, subjects had no such set to experience subjective contours. When two of the containing patterns that had been used in the first experiment were shown, no subjective contours were perceived. However, after subjects had been familiarized with a drawing of one of the fitting shapes, they saw that shape in the pattern that contained it and along with it the subjective contours. © 1988 Psychonomic Society, Inc.