Edge-Region Grouping

Published As:

Palmer & Brooks (2008). Edge-Region Grouping in Figure-Ground Organization and Depth Perception. Journal of Experimental Psychology: Human Perception & Performance, 34(6), 1353-1371

Abstract:

A new class of information about depth across an edge and figure-ground organization - edge texture grouping - is described and demonstrated. The central issue in both cases is whether the edge between two regions "belongs to" (or "is grouped with") one side or the other. The side that is grouped with the edge should be perceived as closer and shaped by the edge, whereas the ungrouped side should be perceived as farther away and extending (unshaped) behind the edge. This analysis implies that classic grouping factors that relate various edge properties to corresponding textural properties within adjacent regions should systematically influence perceived depth across an edge and figural status. We report the results of several experiments that strongly support this claim for the grouping factors of common fate, proximity, synchrony, and similarity of blur, color, and orientation. Further, we argue that evidence of grouping in certain moving and flickering displays that are ecologically unnatural suggest that these effects are mediated by grouping processes rather than by inferences based on simple ecological statistics. The edge-texture grouping hypothesis provides a unified account of the present phenomena and others previously reported in the depth perception literature (e.g., Yonas, Craton & Thompson, 1987) as well as a coherent explanation of Weisstein's anomalous findings about the effects of spatial frequency and flicker on depth and figural status (e.g., Klymenko & Weisstein, 1986). Edge-texture grouping effects have important implications for depth and shape algorithms in computer vision as well as for corresponding perceptual and neural processes in human vision.