Social Behavior

Oxytocin (OXT), a neuropeptide synthesized in the paraventricular nucleus (PVN) of the hypothalamus, functions to increase the precedence of social stimuli and promote the development of a wide range of social behaviors. However, whether OXT has a predicting role in social reward has yet to be examined. In this study, we developed a genetically encoded, scalable OXT sensor named OXTR-iTango2 and applied this technique to define the role of OXT in learned social behaviors. OXTR-iTango2 enables the combination of light- and ligand- dependent gene expression both in vitro and in vivo neural systems. In order to study the predictive role of OXT during expected socially rewarding experiences, we first conditioned animals to a social environment, and then selectively labeled OXT-sensitive ventral tegmental area dopamine (VTA-DA) neurons when animals encountered a conditioned stimulus that stood to predict a familiar social reward. Recurrent exposure to the same social stimulus normally lowered the degree of social interaction, but this reduced interaction was not observed when OXT-sensitive DA neurons were optogenetically inhibited. Thus, our findings support the notion that OXT plays a role beyond promoting social interactions, leading for a new proposed hypothesis that OXT mediation also leads to active avoidance of mundane social interactions.

The current studies examined the interplay of dominance and power in their effects on various forms of prosociality, along with potential mechanisms that may account for their differential effects. Study 1 found that dominance and power had opposing effects on general prosocial tendencies, with dominance negatively relating to and power positively relating to general prosociality. Study 2 found the negative effects of dominance to be consistent both for general and relationship-specific prosociality. The effects of power were not replicated for the outcomes shared with Study 1, but other positive associations were found between power and prosocial propensities. Indirect effects in studies 1 and 2 supported the potential mediating role of other focus in explaining the differential effects of dominance and power. Study 3 utilized an experimental design to directly examine the potential mediating role of other-focus, by manipulating independent versus interdependent self-construals. Significant interactions between power and condition supported the notion that power positively affects prosociality by increasing other-focus. In the interdependent condition, power significantly predicted perspective-taking, whereas in the independent condition, the effect of power on perspective-taking was not significant. Study 4 involved collecting dyadic data from romantic partners, but did not find any significant partner effects. In line with the other studies, dominance was negatively associated with self-reported supportive tendencies as well as self-reported perceptions of a partner’s supportive behaviors.