Impact of emotion and gaze direction on attentional orienting: Behavioral and electrophysiological evidence

Three experiments examined the behavioral and electrophysiological correlates of the impact of facial expression and gaze direction on attentional orienting. In Experiments I a and 1b, behavioral responses and event-related potentials (Experiment 1b) were recorded in response to peripherally presented targets which followed a centrally presented facial cue depicting both a fearful or neutral expression and either a leftward or rightward gaze. Participants in both experiments showed a consistent pattern of Reaction Time (RT): Fearful cue < Neutral cue; Leftward gaze < Rightward gaze; and Right Visual Field (RVF) < Left Visual Field (LVF). Additionally, participants showed shorter RTs for validly cued LVF targets. ERP analysis revealed several sequential effects: (1) an early enhancement of target processing following fearful faces (P1); (2) an interaction between expression and gaze (N1), with enhanced target processing following fearful faces with rightward gaze; and (3) an interaction between gaze and target location (P3), with enhanced processing for invalidly-cued LVF targets. In Experiment 2 the neutral expression was replaced with Happy to investigate the effects of different emotions on gaze directed attentional orienting. Additionally, nonemotional targets were replaced with emotionally salient targets (a baby or a snake). Behaviorally, participants responded faster to validly-cued targets and fear cued targets in the RVF. Three sequential ERP components were modulated by happy emotion, including: (1) larger P1 amplitude over contralateral occipital sites for targets following happy faces; (2) larger centrally-distributed N1 amplitude for targets following happy faces with leftward gaze; and (3) faster P3 latency for baby targets. Additionally, P3 amplitude was reduced for valid targets following fearful expressions (expression by validity interaction). Collectively, these results support three conclusions. First, two nonverbal social cues---facial expression and gaze direction---modulate attentional orienting across different temporal stages of processing. Second, attentional broadening and motivational approach are induced in the presence of happy emotion, and third, facilitation of spatially-directed attention occurs in the presence of fearful cues. The findings have implications for understanding how socioemotional signals in faces interact with each other and with emotional features of objects in the environment to alter attentional processes during dyadic exchanges.