OBJECT RECOGNITION CONTRIBUTIONS TO FIGURE GROUND ORGANIZATION - OPERATIONS ON OUTLINES AND SUBJECTIVE CONTOURS

In previous research, replicated here, we found that some object recog nition processes influence figure-ground organization. We have propose d that these object recognition processes operate on edges (or contour s) detected early in visual processing, rather than on regions. Consis tent with this proposal, influences from object recognition on figure- ground organization were previously observed in both pictures and ster eograms depicting regions of different luminance, but not in random-do t stereograms, where edges arise late in processing (Peterson & Gibson , 1993). In the present experiments, we examined whether or not two ot her types of contours-outlines and subjective contours-enable object r ecognition influences on figure-ground organization. For both types of contours we observed a pattern of effects similar to that originally obtained with luminance edges. The results of these experiments are va luable for distinguishing between alternative views of the mechanisms mediating object recognition influences on figure-ground organization. In addition, in both Experiments 1 and 2, fixated regions were seen a s figure longer than nonfixated regions, suggesting that fixation loca tion must be included among the variables relevant to figure-ground or ganization.