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Perceiving depth in point-light actions.

Jan Vanrie·Karl Verfaillie
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Abstract

The present study investigates how observers assign depth in point-light figures, by manipulating spatiotemporal characteristics of the stimuli. Previous research on the perception of point-light walkers revealed bistability (i.e., that a point-light walker is perceived as either facing the viewer or facing away from the viewer) and the presence of a perceptual bias (i.e., a tendency to perceive the figure as facing the viewer). Here, we study the generality of these phenomena by having observers indicate the global depth orientation of different ambiguous point-light actions. Results demonstrate bistability for all actions, but the presence of a preferred interpretation depends strongly on the performed action, showing that the process of depth assignment takes into account the movements the point-light figure performs. Two additional experiments, using unfamiliar movement patterns without strong semantic correlates, show that purely kinematic aspects of a naction also strongly affect d epth assignment. Together, the results reveal the perception of depth in point-light figures to be a flexible processinvolving both bottom-up and top-down components.

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Depth PerceptionExtremitiesHumansLightMotion PerceptionMovementVisual PerceptionJournal ArticleResearch Support, Non-U.S. Gov't

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Jan Vanrie, Karl Verfaillie. 2006. Perceiving depth in point-light actions.. https://doi.org/10.3758/bf03208762

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