Oxytocin differentially modulates eye gaze to naturalistic social signals of happiness and anger.

A number of previous studies has shown that oxytocin (OT) promotes facial emotion recognition and enhances eye gaze to facial stimuli in humans. Other studies report valence-specific effects of OT, supporting the proposed prosocial role of OT in social interactions. In the present study, we tested the hypothesis whether OT might selectively enhance eye gaze to positive, approach-related, but not to negative, threat-related social cues. In a placebo-controlled, double-blind, between-subject design, we assessed the effects of intranasal OT administration (24 IU) in 62 healthy male volunteers on eye gaze toward the eyes of neutral, positive (happy) and negative (angry) facial expressions compared with placebo. In order to capture the dynamics of facial expressions, we used video sequences showing neutral faces gradually displaying a specific emotion. In line with previous studies, OT increased eye gaze toward neutral facial expressions. Moreover, under OT treatment, eye gaze remained increased when the face showed a happy facial expression, but in contrast decreased when the face displayed an angry expression. These results support the notion that OT differentially modulates visual attention toward social signals of positive approach and threat and thereby contributes to the modulation of non-verbal interpersonal communication.