Abstract
Previous research has suggested that the appearance of an occluder allows discrete objects to be completed into a continuous object. In the present experiments, we examined the role of visual working memory (VWM) in amodal completion using a dual task paradigm in which participants performed an object-based attention task while maintaining four colors in working memory. Four discrete rectangles were displayed, followed by an occluder that allowed the four rectangles to be completed into two large rectangles. Before the occluder appeared, four to-be-remembered color-patches were presented either in the ends of each rectangle (Experiement1) or outside of the rectangles (Experiment 2). When the colors appeared in the objects and needed to be remembered (dual task), object-based attentional effects based on amodal completion were eliminated. Importantly, amodal completion was prevented or slowed only when the color patches needed to be remembered; when the object-based attention task was performed alone (single task), object-based attentional effects based on amodal completion were observed. When the colors were presented outside of objects, however, object-based attentional effects based on amodal completion persisted. VWM interferes with amodal completion when the memory contents are presented on the objects to be completed, suggesting that amodal completion may not be ‘automatic’ and can be affected by high-level visual processes.
Supported by National Science Foundation award BCS 99-10727 and National Institutes of Health award MH60636