Emotion perception, inferring the emotional state of another person, can be formalized as decision under uncertainty: another person's scowling face may indicate anger or concentration and the optimal inference is contingent on the decision consequences (payoff) and how likely real anger is encountered (base rate). Although emerging evidence suggests that the neuropeptide oxytocin influences human perception of emotional facial expressions, whether such effect relates to the alternated process of payoff or base rate still remains unclear. In addition, little is known about oxytocin's effect on metacognitive process involved in emotion perception. One hundred and twenty-two healthy male adults (sixty-two in Experiment 1 and sixty in Experiment 2, respectively) received 24 international units (IU) of intranasal oxytocin or placebo (between-subjects) in a randomized and double-blind study. We independently and systematically manipulated the payoff and base rate levels in an emotion categorization task and measured participants' response bias via categorization choice and metacognitive sensitivity via confidence report. Compared to the placebo group, oxytocin specifically induced a categorization bias under the payoff, but not base rate manipulation. In contrast, oxytocin had no effect on subjects' confidence rating, indicating that the metacognitive sensitivity can be dissociated from emotion perception. Our results pinpoint the specific role of oxytocin in payoff evaluation, but not target likelihood estimation and provide a potential theoretical framework to bridge oxytocin research in emotion perception, social cognition and value-based decisions.

中文翻译：

---

催产素改变情绪感知的回报效应，而不是基础率

情绪感知，推断另一个人的情绪状态，可以被形式化为不确定性下的决策：另一个人的皱眉可能表明愤怒或专注，而最佳推断取决于决策结果（回报）以及遇到真正愤怒的可能性（基础）速度）。尽管新出现的证据表明神经肽催产素会影响人类对情绪面部表情的感知，但这种影响是否与回报或基本比率的交替过程有关仍不清楚。此外，关于催产素对涉及情绪感知的元认知过程的影响知之甚少。122 名健康成年男性（实验 1 中的 62 名和实验 2 中的 60 名，分别）在一项随机和双盲研究中接受了 24 国际单位 (IU) 的鼻内催产素或安慰剂（受试者之间）。我们独立且系统地操纵情绪分类任务中的回报和基本率水平，并通过分类选择和通过置信报告的元认知敏感性测量参与者的反应偏差。与安慰剂组相比，催产素特别在收益下引起分类偏差，但不会在基本速率操纵下引起分类偏差。相比之下，催产素对受试者的信心等级没有影响，表明元认知敏感性可以与情绪感知分离。我们的结果确定了催产素在收益评估中的具体作用，