Comparisons of the neural mechanisms of voluntary, reflexive, and socially-directed attention

Visual attention serves to select, from amongst a huge influx of visual information, an item or location to receive greater processing. This focus of attention can be directed voluntarily or it can be reflexively captured by a sudden onset or movement. In recent years another type of attentional orienting has been studied: "social gaze orienting". In this type of orienting, the gaze of another person automatically causes one's attention to shift in the direction of the gaze. While this attentional shift is automatic in nature, its properties differ from those typically associated with reflexive orienting, especially on terms of the timing of facilitation effects. The relations between social gaze cueing, voluntary cuing, and reflexive cueing are not well understood. The current study explores the similarities and differences between the neural mechanisms of these types of orienting using event-related potentials (ERPs). ERPs allow us to explore differences in the neural underpinnings of voluntary, reflexive, and social gaze orienting that may or may not be exhibited in overt behavior. In Experiment 1, it was discovered that a localization task at cue-target SOAs of 50-250 and 300-500ms was able to produce significant effects on behavior. In Experiment 2, when timing was the same for each type of attention (an SOA of 300-500ms), behavioral and early visual ERP effects were similar for social and voluntary attention, but reflexive attention showed a different pattern. In Experiment 3, when timing is varied for each type of attention, producing the strongest effects on behavior, greater differences between social and voluntary cuing emerged, as social attention no longer showed any significant effects on early visual ERPs. In both ERP experiments social attention showed increased amplitude for invalid targets on late negative component peaking around 420ms after the target. For reflexive and voluntary attention, in both experiments, this effect is either absent or reversed suggesting that continued processing that occurs after target response is distinct for social attention. These new findings suggest that while more similar to voluntary attention, social attention shows distinct processing at some levels, suggesting it should not be considered equivalent to reflexive or voluntary attention.