Event coding and motor priming: how attentional modulation may influence binding across action properties

When we perceive an action it is internally transformed into a motor representation akin to the execution of that same action. Motor priming studies show that action observation facilitates the execution of physically similar actions, but interferes with the performance of dissimilar actions. Some evidence suggests, however, that once a specific motor plan is formed, perceiving an action with partially overlapping features (e.g. a congruent grip-type but and incongruent end-goal) can result in interference. In two experiments we investigate how modulating attention towards observed actions influences the binding that occurs between action features, and therefore the amount of partial-overlap interference to participants' performance. In the first study we directed attention towards a salient action feature (the grip-type). We found that perceiving partially overlapping (i.e. partially congruent) actions slowed participants' responses compared with observation of completely congruent or incongruent actions. In the second experiment attentional resources were taxed through the use of a secondary task. This resulted in the elimination of the partial-overlap interference effect. We discuss results in relation to feature binding and event codes.