What do we see behind an occluder? Amodal completion of statistical properties in complex objects

Abstract

When a spiky object is occluded, we have the compelling percept that its spiky features continue behind the occluder. Although many real-world objects contain complex features, it is unclear how their features are amodally completed and whether this process is automatic. To this end, we asked participants to search for oddball targets among distractors and asked whether similarity relations in visual search between occluded displays match better with global or local completions of these displays. In Experiment 1, when objects with curved/straight corners were occluded, they were perceived as continuing with the same features than with them exchanged. In Experiment 2, we obtained similar results for objects with irregular/symmetric features. Analogous investigations on deep neural networks revealed similar results for curved/straight contours but not for irregular/symmetric features. Thus, amodal completion involves extending not only simple contours, but also their more global statistical properties.