Recent experiments have cast considerable doubt upon the ability of color singletons to capture spatial attention in a stimulus-driven manner. Despite the lack of evidence for it in the laboratory, there are many anecdotal reports of stimulus-driven capture in real-world settings. Perhaps a critical difference between laboratory and real-world visual scenes is the amount of relevant information, or perceptual load. Scenes with low perceptual load (as when one is focused on a single visual object) might free attentional resources, allowing them to be more easily captured by color singletons. To test this hypothesis, we manipulated perceptual load in a visual search task with irrelevant flanking letters that were sometimes color singletons. If reduced perceptual load increases susceptibility to capture by color singletons, then the presence of a color singleton should slow responses and increase flanker-target compatibility effects. Contrary to this prediction, we found no evidence of capture under high or low perceptual load
