Mechanisms for action prediction operate differently in observers with motor experience

Recent theoretical and empirical work has suggested an important role for the motor system in generating predictions about the timing of external events. We tested the hypothesis that motor experience with an observed action changes how observers generated predictions about these actions by comparing the performance of naive and experienced observers on a task that required participants to predict the timing of particular critical points in a ongoing observed action. Crucially, we employed action and non-action stimuli with identical temporal dynamics, and we predicted that motor experience would enhance prediction accuracy specifically for actions and would have a reduced or negligible effect on enhancing prediction accuracy for non-action stimuli. Our results showed that motor experience did modulate prediction accuracy for action stimuli relative to non-action stimuli. No difference between conditions was observed for the naive observers.