Abstract: Prosocial behavior can enhance the group's functionality, and improve positive emotions in both perpetrators and recipients. However, traditional prosocial behaviors were not primarily focusing on the perception of other's needs and wish. Correspondingly, social mindfulness is being taking care of others in the present moment, and respecting rights of others when making a decision. Therefore, it is considered as a kind of low-cost prosocial behavior, which offers a new perspec-tive for exploring how to promote a person's prosocial motivation. Oxytocin is the neurobiologi-cal hormone of prosocial behavior and some studies indicated that the effects of oxytocin on pro-social behavior were moderated by contextual factors. As a most available information in social contexts, facial attractiveness has an important influence on prosocial behavior. Therefore, the aims of the present study are to explore whether oxytocin could promote social mindfulness and whether initial relationships are influenced by facial attractiveness and gender of interaction part-ners. To examine the effects of oxytocin on social mindfulness, two double-blind plac-bo-controlled experiments were conducted. The social mindfulness (SoMi) paradigm was used to assess social mindfulness, in which participants made decisions that either limited (selected the unique one from the 4 objects) or preserved the choices of options (selected one of the 3 same objects from the 4) for the subsequent fictitious interaction partners. Study 1 recruited 58 healthy Chinese male college students who self-administered either 24 IU of oxytocin or a placebo in-tranasally first. Then, they completed SoMi paradigm with their “partner” (5 medium attractive-ness male faces and 5 medium attractiveness female faces). On each trail, the participants were instructed to look at his partner’s face first and then choose one of the four objects, after which his “partner” choose one from the remaining three objects. The results showed that compared to par-ticipants receiving the placebo, participants receiving oxytocin showed higher social mindfulness, regardless of the partner’s gender. To further explore the effect of facial attractiveness on the rela-tionship between oxytocin and social mindfulness, we manipulated the degree of facial attrac-tiveness of the partner in Study 2 (70 healthy Chinese male college students) by same procedure with Study 1. The results showed that: (1) compared to participants receiving the placebo, partic-ipants receiving oxytocin showed higher social mindfulness; (2) participants showed higher so-cial mindfulness to their partners with high facial attractiveness rather than those with low face attractiveness, and the difference in social mindfulness between high attractiveness female and low attractiveness female was greater than that between males; (3) there was no significant inter-action between oxytocin and facial attractiveness on social mindfulness. In conclusion, the current two studies demonstrated that the intranasal administration of ox-ytocin could enhance social mindfulness regardless of facial attractiveness. For social mindfulness, men seemed to be more sensitive to facial attractiveness of the opposite sex. It confirms the role of oxytocin in promoting prosocial behavior in an extended field.

Key words: social mindfulness, oxytocin, facial attractiveness, prosocial behavior

摘要： 两个实验考察催产素对社会善念的作用以及面孔吸引力对二者关系的影响。实验1采用双盲实验，使用安慰剂作对照，发现催产素可以促进社会善念，不受面孔性别的影响。实验2依然采用双盲实验，进一步考察面孔吸引力与面孔性别对催产素与社会善念关系的作用，发现催产素对社会善念的作用不受面孔吸引力的影响；女性面孔（与男性面孔相比）吸引力对男性的社会善念影响更大。研究表明，催产素可以稳定地提高社会善念水平。

关键词: 社会善念, 催产素, 面孔吸引力, 亲社会行为