Investigating local and global effects of surface colours and contours in amodal completion

Abstract

We studied interpretations of partly occluded shapes. Models that account for amodal completion mostly deal with local and global contour characteristics. In the current study, we were interested in the effects of colour on local and global contour completions. In our stimuli, local contour completions comprised simple linear extensions of the partly occluded contours, whereas global contour completions accounted for global shape regularities. Our stimuli were designed such that the visible surface colour could also be completed in a local or global fashion, being consistent or inconsistent with contour completions. We tested the preferred interpretations of the partly occluded shapes by using a sequential matching task. Participants had to judge whether a test shape could be a previously shown partly occluded shape. We found that interpretations of partly occluded shapes depend on both colour and contour characteristics. Additional time bin analyses revealed that for fast responses colour and contour completions already depend on the visible context of the partly occluded shapes, while for slow responses the congruency between colour and contour completions play a role as well.

Completeness out of incompleteness: Inferences from regularities in imperfect information ensembles.

“…The filling-in process is mainly achieved by extracting the regularities of the already-known parts and interpolating the recoveries derived from these regularities. Just as the subobject deficiencies of obscured solitary objects can be supplemented by intra-object regularity (visual interpolation theory, Kellman & Shipley, 1991; Gestalt configuration laws and surface features, Yun et al, 2018b), group-level deficiencies of partially absent object clusters can be fixed by inter-object regularities, including statistical properties, configurations, and spatial regularities (i.e., various sources of information serving as clues to construct major hidden parts). While entity properties might play an essential role in the completion of a solitarily obscured object, the regularities of a stimulus cluster underscore the information not inherent within single individuals but which exists in the abstract relations among them.…”

Amodal Completion of Color

“…To sum up, these demonstrations suggest that the experience of amodal completion in Figure 3A incorporates the following four distinguishable aspects: existence beyond occluding boundaries, singleness of occluded figure, continuation of contour directions, and equality of color. Previous research on amodal completion was in large part devoted to amodal completion of contours, and although amodal completion of surfaces has also been studied, not much attention was addressed to amodal completion of their color (but see Yin, Kellman, & Shipley, 1997;Anderson et al, 2002;Pinna, 2008;Yun, Hazenberg, & van Lier, 2018).…”