and pair bonding to OXTR variation (Walum et al., 2012). Socially relevant characteristics including callus-unemotional traits (Cecil et al., 2014; Rice & Derish, 2015), orientations toward individualism vs. collectivism (Luo & Han, 2014), aggressiveness (Wu, Li, & Su, 2012), and low empathy (Feldman et al., 2015) have all been linked to OXTR. Oxytocin also has been linked to prosocial behaviors, but in a contextually moderated fashion (Bartz et al., 2011); enhancing prosociality in cooperative contexts but increasing aggression in competitive contexts (id.). In this way, oxytocin appears to facilitate groupism—in-group bonding and out-group distinction (see Shamay-Tsoory & Abu-Akel, 2015; also Feldman et al., 2015). Thus, the impacts of genetic variation linked to oxytocin on social behaviors are likely context-sensitive.
