从着装规定和餐桌上的礼仪到税收及联邦法律，社会规范一直是人类文明的一个标志。纵观历史，人类一直通过威胁要惩罚那些不遵守社会规范的人来实施社会规范。如今，研究人员已经查明了一个被称为右外侧前额叶皮层(rLPFC)的特别脑区——rLPFC控制着对社会规范的遵从——无论是在对这些规范的采纳是自愿的还是在当受到惩罚威胁时。Christian Ruff及其同事用一种叫做经颅直流电刺激的技术来增强或降低在一个游戏中的63名研究参与者的rLPFC的活动；在该游戏中，参与者相互之间会转移金钱并会相互威胁如果所收到的钱的数量太小的话会给予制裁。Ruff及其他的研究人员发现，当rLPFC中的活性增强时——且当受到其他玩家以制裁威胁时——研究的参与者会给其他参与者显著地转了更多的金钱。他们说，另一方面，当rLPFC中的活动减少时--即使当受到制裁威胁时--参与者转给其他玩家的钱会显著变少。有趣的是，当转钱完全是自愿且不涉及制裁时，参与者会做出相反的事情——当他们rLPFC的活动增强时会转较少的钱，而当他们rLPFC的活动减少时会转更多的钱。研究人员还发现，当研究的参与者是与电脑而不是与其他人来玩该游戏时，刺激rLPFC所施加的影响会弱得多，提示rLPFC要影响社会规范的遵守可能需要有一个社会环境。这些发现提示，rLPFC构成了人类行为的一个古老而且重要的方面，且它们可能会导致对以不遵守社会规范为特征的某些精神疾病及神经疾病（更不用提犯罪活动）的新的了解。（生物谷 Bioon.com）
生物谷推荐的英文摘要
Science DOI: 10.1126/science.1241399
Changing Social Norm Compliance With Noninvasive Brain Stimulation
C. C. Ruff1,*, G. Ugazio1,2, E. Fehr1,*
All known human societies have maintained social order by enforcing compliance with social norms. The biological mechanisms underlying norm compliance are, however, hardly understood. We show that the right lateral prefrontal cortex (rLPFC) is involved in both voluntary and sanction-induced norm compliance. Both types of compliance could be changed by varying neural excitability of this brain region with transcranial direct current stimulation, but they were affected in opposite ways, suggesting that the stimulated region plays a fundamentally different role in voluntary and sanction-based compliance. Brain stimulation had a particularly strong effect for compliance based on socially constituted sanctions, while it left beliefs about what the norm prescribes and about subjectively expected sanctions unaffected. Our findings suggest that rLPFC activity is a key biological prerequisite for an evolutionarily and socially important aspect of human behavior.
