The uniqueness of social attention revisited: working memory load interferes with endogenous but not social orienting.

It is well known that perceived eye gaze direction influences attentional orienting. However, it still remains unclear whether social orienting involves exogenous or endogenous attentional control. To address this issue, we examined if social orienting and endogenous orienting were differentially modulated by working memory load, which is known to interfere with endogenous but not exogenous attention. To do so, we manipulated eye direction as either spatially counterpredictive in Experiment 1 or spatially predictive in Experiment 2 while participants performed a cueing task either in isolation or under working memory load. We found that when social attention and endogenous attention diverged spatially in Experiment 1, social orienting elicited by gaze direction remained intact while endogenous orienting elicited by the cue's predictive meaning was suppressed under working memory load, suggesting independence between social orienting and endogenous orienting. Indeed, a comparison between the sum of isolated social orienting and endogenous orienting magnitudes from Experiment 1 relative to their combined measure from Experiment 2 confirmed that social attention and endogenous attention operated in parallel. Together, our data show that social orienting is independent from endogenous orienting and further suggest that paying attention to social information might involve either exogenous or unique attentional mechanisms.