Effect of intranasal oxytocin on pro-social behavior in social anxiety disorder
Previous research suggests that intranasal oxytocin may promote trust, social cooperation, in-group favoritism, and empathic concern in humans. Oxytocin therefore has therapeutic implications for psychological disorders such as social anxiety disorder (SAD). In particular, oxytocin may have anxiety-buffering effects in the context of social rejection. Oxytocin may promote cooperative social behavior with other individuals despite being rejected by them, as research has shown that oxytocin facilitates decisions indicative of sustained trust even despite breaches of trust. Using a double-blind, placebo-controlled design, the current investigation examined whether oxytocin modulates responses to social rejection from an initially cooperative confederate, and whether it modulates attentional processes toward social stimuli (disgust, neutral, and happy face stimuli). Participants were 54 individuals with SAD, who were randomly assigned to receive 24 international units (IU) of oxytocin or placebo nasal spray. Following drug administration, participants completed a computerized ball-tossing game called Cyberball, in which they were led to believe that they were playing "on-line" with three other fictitious players. The amount of reciprocation displayed by other players was manipulated, such that Player 1 was programmed to play cooperatively during the first half of the game (tossed 70% of his balls to the participant), and then switched to less cooperative play during the second half (tossed 10% of balls to the participant). After Cyberball, participants completed a modified version of the Posner Task. Results showed that oxytocin improved cooperation with Player 1 in the second half of the game, but only for individuals with low attachment avoidance. Oxytocin also amplified subjective ratings of perceived rejection by others during Cyberball for individuals with high rejection sensitivity. Furthermore, oxytocin led to facilitated disengagement from all social cues regardless of emotional valence and speeded up detection of disgust and neutral faces, compared to placebo, but only for individuals with high attachment avoidance. These findings suggest that oxytocin may promote social cooperation, as well as a flexible attentional pattern toward social cues, at least for some individuals with SAD. Future research should address individual differences in responses to oxytocin, and further investigate the comparative effects of oxytocin in healthy individuals.