The sustenance and retention of perspectival shape representations

When we are presented with a coin rotated in depth, although we perceive its objective circular shape, the original perspectival shape is nonetheless represented in the visual system. Here we investigated the onset time and duration of such perspectival representation by systematically manipulating stimuli presentation time vs. post-stimuli retention time. Participants performed a speeded search task and had to find an oval target against a circle distractor that is either head-on (i.e., perspectivally dissimilar) or rotated leftward/rightward (i.e., perspectivally similar). We found that even when stimuli disappeared from view, participants still took more time in locating the oval target, suggesting robust and persistent perspectival interference (Experiment 1). This interference emerged as early as 100 ms (Experiment 2), and persisted for at least 1000 ms (Experiment 3). Together, these results suggest a 100 ms formation time and possibly 1000 ms or longer life span for perspectival representation.