Experience-dependent perceptual grouping and object-based attention.

... this article extend these findings, showing that object attention benefits---shorter reaction times to features appearing on a single object---apply to recently viewed novel shapes. One experiment shows that object attention operates even when the visible fragments correspond to objects that violate standard completion heuristics. Other experiments show that experience-dependent object benefits can apply to fragments even without evidence of occlusion. These results attest to the flexible operation of the perceptual system, adapting as a function of experience.