Predictive processing in visual perception of actions: The modulation of short-term priors by the long-term prior

Predictive processing theories suggest that perception is shaped by prior knowledge, with long-term priors formed through lifelong experiences and short-term priors emerging from immediate contextual cues. Although prior research has explored the influence of expectations on action perception, the interaction between short-term and long-term priors remains understudied. This study examines how these priors interact in visual action perception by embedding animated human and robot agents within a probabilistic-cueing paradigm. Participants observed agents performing biological or mechanical motion, with cues providing either form-based or motion-based short-term priors. Behavioral results showed that long-term priors guided perceptual decisions across conditions when the target stimuli were congruent with them. When expectations were violated, performance patterns reflected a greater weighting of motion-based short-term cues, while form-based cues contributed minimally. These findings highlight the hierarchical nature of predictive processing in action perception, and the precision assigned to different priors is adjusted according to context, favoring motion-based information instead of form-based when resolving perceptual ambiguity.