Abstract
Previous research had shown how simple action towards an object (prime) can help prioritize the allocation of attention onto the same object in the later unrelated visual search task (Weidler & Abrams, 2014). This so-called “action effect” yielded reaction time (RT) benefit only when the target was embedded in the acted-on object. To explore the role of attention in action effect, we examined the allocation of attention at the precise moment of action. In experiment 1, participants were instructed to respond (go) when the prime (colored circle) appeared, and not to respond (no-go) when “X” was on the prime. Next, participants searched for a tilted bar (target), which could appear on the same colored object (valid) or different colored object (invalid). Analysis results showed that the validity effect in experiment 1 was larger for trials with action, replicating the action effect. In experiment 2, participants were instructed not to respond when the prime appeared alone, and to respond when “O” was on the prime. Participants then engaged in the same visual search task as the first experiment. In contrast to experiment 1, analysis results did not show action effect in experiment 2, contributing to the overall significant three-way interaction between action, validity, and experiment. We interpreted that action alone did not benefit subsequent visual search. In experiment 2, action effect was not observed perhaps because attention was located on “O” and action was made toward “O” not the prime. Therefore, it seems that the attended object and the acted-on object match to produce action effect. Furthermore, we suggest that action effect is not just due to the presence of action, but a product of selective attention accompanied by action toward an object.