Abstract
The ability to perceive objects as alive is a fundamental ability that begins early in infancy, has dedicated neural circuitry, and serves as a building block for later social perceptual development. Previous research has shown that one cue to an object's animacy is its speed: Relatively faster moving objects are more likely to be perceived as animate, all else equal. Our goal was to test whether the perception of animacy could be influenced by an illusory difference in speed, in the absence of any actual difference in speed. In a two-alternative forced choice task, participants viewed dots moving one at a time across the two equally-sized central circles of the Ebbinghaus-Titchener illusion. In this illusion, an apparently smaller central circle is surrounded by larger inducing circles, and an apparently larger central circle is surrounded by smaller inducing circles. On each trial, participants saw two dots, one at a time, traveling an equal distance across each of the central circles at one of three constant speeds. Participants judged which of the two dots appeared to be alive. Results showed that of two dots traveling at the same speed across circles of equal diameter, one was perceived as animate significantly more often if moving across an apparently larger circle, for all speeds tested. These results suggest that the perception of animacy can be influenced by the apparent extent of motion in the absence of any actual speed differences.
National Sciences and Engineering Research Council of Canada (NSERC)