Department of Psychology, University of Oslo, Postboks 1094, Blindern 0317, Oslo, Norway.
Soc Cogn Affect Neurosci. 2013 Oct;8(7):741-9. doi: 10.1093/scan/nss062. Epub 2012 May 29.
Sensing others' emotions through subtle facial expressions is a highly important social skill. We investigated the effects of intranasal oxytocin treatment on the evaluation of explicit and 'hidden' emotional expressions and related the results to individual differences in sensitivity to others' subtle expressions of anger and happiness. Forty healthy volunteers participated in this double-blind, placebo-controlled crossover study, which shows that a single dose of intranasal oxytocin (40 IU) enhanced or 'sharpened' evaluative processing of others' positive and negative facial expression for both explicit and hidden emotional information. Our results point to mechanisms that could underpin oxytocin's prosocial effects in humans. Importantly, individual differences in baseline emotional sensitivity predicted oxytocin's effects on the ability to sense differences between faces with hidden emotional information. Participants with low emotional sensitivity showed greater oxytocin-induced improvement. These participants also showed larger task-related pupil dilation, suggesting that they also allocated the most attentional resources to the task. Overall, oxytocin treatment enhanced stimulus-induced pupil dilation, consistent with oxytocin enhancement of attention towards socially relevant stimuli. Since pupil dilation can be associated with increased attractiveness and approach behaviour, this effect could also represent a mechanism by which oxytocin increases human affiliation.
通过微妙的面部表情感知他人的情绪是一项非常重要的社交技能。我们研究了鼻内催产素治疗对明确和“隐藏”情绪表达评估的影响，并将结果与个体对他人愤怒和幸福微妙表达的敏感性差异相关联。40 名健康志愿者参与了这项双盲、安慰剂对照的交叉研究，结果表明，单次鼻内催产素（40IU）增强或“锐化”了对他人积极和消极面部表情的评估处理，无论是明确的还是隐藏的情绪信息。我们的研究结果指向了催产素在人类中产生亲社会影响的机制。重要的是，情绪敏感性的个体差异预测了催产素对感知隐藏情绪信息的面孔之间差异的能力的影响。情绪敏感性低的参与者表现出更大的催产素诱导改善。这些参与者的任务相关瞳孔扩张也更大，这表明他们也将最多的注意力分配给了任务。总体而言，催产素治疗增强了刺激引起的瞳孔扩张，这与催产素增强对社会相关刺激的注意力一致。由于瞳孔扩张可能与吸引力和接近行为的增加有关，因此这种效应也可能代表了催产素增加人类亲和力的一种机制。
