Abstract
Visual working memory capacity for shapes is dependent on the complexity of the shapes stored (Alvarez & Cavanagh, 2004). Consequently, it is important for the visual system to discover regularities and exploit them to form more efficient representations of complex shapes. Some regularities, like symmetry, are perceived efficiently, but the detection and encoding of other regularities may require extended viewing if the shapes are sufficiently complex (Baylis & Driver, 2001). Together, these results suggest that, during initial viewing of novel shapes, the visual system may be discovering regularities and building representations that utilize these regularities. Here we investigate the formation of visual working memory representations of novel shapes. We show that the formation of 2D contour shape memory traces can occur over relatively long time scales (several seconds) and involve integration of shape information across multiple views. Using a novel change detection paradigm in which subjects try to determine if a flickering movie of a single 2D contour shape is slowly changing, we show that large cumulative changes often go undetected. Our results demonstrate that this effect is not due to insufficient visual memory capacity or durability. Rather, it appears to be the consequence of automatic updating of the shape representation. To support this hypothesis, we show that, even when subjects are explicitly instructed to encode the initial shape of a morph sequence, viewing the sequence causes the memory of that initial shape to be biased towards the final shape in the sequence.
Meeting abstract presented at VSS 2013