Get real! Resolving the debate about equivalent social stimuli

Gaze and arrow studies of spatial orienting have shown that eyes and arrows produce nearly identical effects on shifts of spatial attention. This has led some researchers to suggest that the human attention system considers eyes and arrows as equivalent social stimuli. However, this view does not fit with the general intuition that eyes are unique social stimuli nor does it agree with a large body of work indicating that humans possess a neural system that is preferentially biased to process information regarding human gaze. To shed light on this discrepancy we entertained the idea that the model cueing task may fail to measure some of the ways that eyes are special. Thus rather than measuring the orienting of attention to a location cued by eyes and arrows, we measured the selection of eyes and arrows embedded in complex real-world scenes. The results were unequivocal: People prefer to look at other people and their eyes; they rarely attend to arrows. This outcome was not predicted by visual saliency but it was predicted by the idea that eyes are social stimuli that are prioritized by the attention system. These data, and the paradigm from which they were derived, shed new light on past cueing studies of social attention, and they suggest a new direction for future investigations of social attention.