Abstract
People readily understand visible objects and events in terms of invisible physical forces, such as gravity, friction, inertia, and momentum. For example, we can appreciate that certain objects will balance, slide, fall, bend or break. This ability has historically been associated with sophisticated higher-level reasoning, but here we explore the intriguing possibility that such physical properties (e.g. whether a tower of blocks will topple) are extracted during rapid, automatic, visual processing. We did so by exploring both the timecourse of such processing and its consequences for visual awareness. Subjects saw hundreds of block-towers for variable masked durations and rated each tower's stability; later, they rated the same towers again, without time pressure. We correlated these limited-time and unlimited-time impressions of stability to determine when such correlations peak — asking, in other words, how long it takes to form a "complete" physical intuition. Remarkably, stability impressions after even very short exposures (e.g. 100ms) correlated just as highly with unlimited-time judgments as did impressions formed after exposures an order-of-magnitude longer (e.g. 1000ms). Moreover, these immediate physical impressions were accurate, agreeing with physical simulations — and doing so equally well at 100ms as with unlimited time. Next, we exploited inattentional blindness to ask whether stability is processed not only quickly, but also spontaneously and in ways that promote visual awareness. While subjects attended to a central stimulus, an unexpected image flashed in the periphery. Subjects more frequently noticed this image if it was an unstable tower (vs. a stable tower), even though these two towers were just the same image presented upright or inverted. Thus, physical scene understanding is fast, automatic, and attention-grabbing: such impressions are fully extracted in (an exposure faster than) the blink of an eye, and a scene's stability is automatically prioritized in determining the contents of visual awareness.
Meeting abstract presented at VSS 2017