The role of characteristic motion in object categorization.

We report three experiments where we investigated the role of movement in object recognition. Previous studies have suggested a distinct and separate mechanism for object motion encoding, related to the action or motor-based system. To date, however, the role of an object's motion in long-term memory representations has not been explicitly tested. Here we were specifically interested in whether an object's characteristic motion patterns are integrated with static properties in an object's representation in memory. To that end, we used a simple categorization task where novel objects were categorized on the basis of two static (color and shape) and two dynamic (action and path) properties. The "action" of an object referred to its intrinsic motion pattern, whereas "path" referred to an object's extrinsic motion pattern (i.e., the route an object took). In Experiment 1, we found that all properties were relevant for categorization with the exception of path. This result was not due to path being less salient than other properties (Experiment 2). In Experiment 3, we found that when the action property was redundant that path was now used for categorization, suggesting that path was not used with action in Experiment 1 because of temporal order effects. Our findings argue for a cue-integrated model of object representation in memory.