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PubMed · 15250665

Perceptual grouping in shape from shading.

Takahiro Kawabe·Kayo Miura
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Abstract

We report on the reversal of asymmetry in visual-search tasks with shaded items. Previous studies have suggested that the target of a bottom-lit disk among distractors of top-lit disks is detected in a rapid and parallel manner, but not vice versa. However, in this study, we have shown that the compound items of top-lit disks were searched more quickly than those composed of bottom-lit disks where the items had to be segregated from their background. By modulating the inter-element distances, we confirmed that the reversal of search asymmetry cannot be due to the grouping of items. Further, we showed that the regions of the top-lit disks were perceived as figure more consistently than those of bottom-lit disks. The results indicate that the boundary assignment to the compound items of the top-lit disks enhances the segregation of search items from the background, and that the search mechanism may access the relatively higher representation that includes figure-ground relations.

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Depth PerceptionFemaleHumansLightingMaleOptical IllusionsPattern Recognition, VisualPhotic StimulationReaction TimeJournal Article

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Takahiro Kawabe, Kayo Miura. 2004. Perceptual grouping in shape from shading.. https://doi.org/10.1068/p3438

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