Task-irrelevant stimulus salience affects visual search.

The relative contributions of stimulus salience and task-related goals in guiding attention remain an issue of debate. Several studies have demonstrated that top-down factors play an important role, as they often override capture by salient irrelevant objects. However, Yantis and Egeth [Yantis, S., & Egeth, H. E. (1999). On the distinction between visual salience and stimulus-driven attentional capture. Journal of Experimental Psychology: Human Perception and Performance, 25, 661-676.] have made the more radical claim that salience plays no role in visual search unless the observer adopts an attentional set for singletons or "singleton-detection mode". We reexamine their claim while disentangling effects of stimulus salience from effects of attentional set and inter-trial repetition. The results show that stimulus salience guides attention even when salience is task irrelevant.