Facial Reactivity and Attentional Processing of Facial Expressions and Gaze Direction

Abstract

Abstract. Patterns of facial reactivity and attentional allocation to emotional facial expressions, and how these are moderated by gaze direction, are not clearly established. Among a sample of undergraduate university students, aged between 17 and 22 years (76% female), corrugator and zygomatic reactivity, as measured by facial electromyography, and attention allocation, as measured by the startle reflex and startle-elicited N100, was examined while viewing happy, neutral, angry and fearful facial expressions, which were presented at either 0- or 30-degree gaze. Results indicated typically observed facial mimicry to happy faces but, unexpectedly, “smiling” facial responses to fearful, and to a lesser extent, angry faces. This facial reactivity was not influenced by gaze direction. Furthermore, emotional facial expressions did not elicit increased attentional allocation. Likewise, matched facial expressions did not elicit increased attentional allocation. Rather, happy and fearful faces with direct (0°) gaze elicited increased controlled attentional allocation, and averted (30°) gaze faces, regardless of emotional expression, elicited preferential, early cortical processing. These findings suggest typical facial mimicry to happy faces, but unexpected facial reactivity to angry and fearful faces, perhaps due to an attempt to regulate social bonds during threat perception. Findings also suggest a divergence in controlled versus preferential, early cortical attentional processing for direct compared to averted gaze faces. These findings relate to young, mostly female, adults attending university. The experiment should be repeated with a larger sample drawn from the general community, with a broader age range and gender balance, and with a stimulus set with validated subjective valence and arousal ratings. This can reduce Type II error and establish normative patterns of facial reactivity and attentional processing of emotional facial expressions with different gaze directions.