Influence of simple action on subsequent manual and ocular responses.

Recent investigations into how action affects perception have revealed an interesting "action effect"-that is, simply acting upon an object enhances its processing in subsequent tasks. The previous studies, however, relied only on manual responses, allowing an alternative stimulus-response binding account of the effect. The current study examined whether the action effect occurs in the presence of changes in response modalities. In Experiment 1, participants completed a modified action effect paradigm, in which they first produced an arbitrary manual response to a shape and then performed a visual search task in which the previous shape was either a valid or invalid cue-responding with a manual or saccadic response. In line with previous studies, the visual search was faster when the shape was a valid cue but only if the shape had been acted upon. Critically, this action effect emerged similarly in both the manual and ocular response conditions. This cross-modality action effect was successfully replicated in Experiment 2, and analysis of eye movement trajectories further revealed similar action effect patterns on direction and numerosity. These results rule out the stimulus-response binding account of the action effect and suggest that it indeed occurs at an attentional level.