The effects of intranasal oxytocin on contagious yawning.

Contagious yawning is thought to represent a basic form of empathy involved in state matching. Despite recent evidence in support of this connection, the neurochemical basis of contagious yawning remains largely unknown. Here, we investigate whether intranasal oxytocin, a hormone and neuropeptide involved in empathic processing, bonding and social affiliation, influences contagious yawning among human participants in a laboratory setting. Using a double blind procedure, 60 male college students received 30 IU of intranasal oxytocin or placebo and were then recorded during exposure to a contagious yawning video stimulus. Contrary to the empathic modeling hypothesis, oxytocin did not increase contagious yawning but rather appeared to modulate its expression in ways indicative of an enhanced awareness of the social stigma associated with this behavior. In particular, individuals in the oxytocin condition were more likely to conceal their yawns and less likely to display overt cues associated with the behavior. Follow-up research could explore how social context and affiliation with the target stimulus alter this response.