One Step Ahead: The Perceived Kinematics of Others' Actions Are Biased Toward Expected Goals

Action observation is often conceptualized in a bottom-up manner, where sensory information activates conceptual (or motor) representations. In contrast, here we show that expectations about an actor's goal have a top-down predictive effect on action perception, biasing it toward these goals. In 3 experiments, participants observed hands reach for or withdraw from objects and judged whether a probe stimulus corresponded to the hand's final position. Before action onset, participants generated action expectations on the basis of either object types (safe or painful, Experiments 1 and 2) or abstract color cues (Experiment 3). Participants more readily mistook probes displaced in a predicted position (relative to unpredicted positions) for the hand's final position, and this predictive bias was larger when the movement and expectation were aligned. These effects were evident for low-level movement and high-level goal expectancies. Expectations bias action observation toward the predicted goals. These results challenge current bottom-up views and support recent predictive models of action observation.