Complex backgrounds delay low-load visual search

Abstract

Past research has shown, separately, that endogenous location cues and high perceptual load search tasks increase the specificity of attentional deployment to task-relevant regions of the visual field, while complex task-irrelevant backgrounds greatly resembling task-relevant stimuli reduce it. Here, we investigated in the same study whether the perceptual load created by an endogenously cued set of task-relevant stimuli determines whether a surrounding complex background of similar task-irrelevant stimuli would interfere with search. Our results show that high perceptual load protects against interference from a complex background of similar but task-irrelevant stimuli, situated just beyond the boundaries of the task-relevant set. Furthermore, our findings demonstrate that search characteristics do not change when the relevant set is restricted attentionally to a smaller delineated area, even in the presence of a background. Finally, we found that the efficacy of endogenous location cueing is not dependent on the type of search task that occurs in the cued area. Our findings also reveal that alternative attention-directing strategies, such as guided search and signal detection, may be employed in such tasks in the absence of endogenous location cueing.