Gender-specific effects of vasopressin on human social communication: An ERP study

The quick and efficient perception of facial expressions represents a special and fundamental capacity of humans to engage in social communication. Here, we examined the effects of vasopressin (AVP, a neuropeptide) on the processing of same- and other-gender facial expressions among males and females. After receiving either AVP or placebo (PBO) intranasally in a randomized and double-blind manner, participants were asked to rate their approachability to facial expressions while event-related potentials (ERPs) were recorded. Males rated lower approachability scores to neutral and positive male faces relative to the scores to emotion-matched female faces after AVP but not following PBO administration. These behavioral effects were correlated with the AVP-induced increased P1 and decreased N170 responses to male faces among male participants. Females rated higher approachability scores to negative female faces than the scores to negative male faces after AVP but not following PBO treatment. These results suggest that AVP decreases friendly responses to neutral/positive male faces in males and increases friendly responses to negative female faces in females. Overall, these results demonstrate the gender-specific effects of AVP in response to same- and other-gender facial expressions, indicating there are sex- and context-dependent effects of AVP on socioemotional processes.