Han Xiaochun, He Kang, Wu Bing, Shi Zhenhao, Liu Yi, Luo Siyang, Wei Kunlin, Wu Xinhuai, Han Shihui
School of Psychological and Cognitive Sciences, PKU-IDG/McGovern Institute for Brain Research, Beijing Key Laboratory of Behavior and Mental Health, Peking University, Beijing, China.
Academy for Advanced Interdisciplinary Studies, Peking University, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, China.
Soc Cogn Affect Neurosci. 2017 Jun 1;12(6):893-901. doi: 10.1093/scan/nsx016.
Empathy has been supposed to be a proximate mechanism of altruistic behavior. We investigated whether empathy for pain drives actions without altruistic effects and how such actions modulate neural responses to others' pain. In two experiments, we asked healthy adults to press a button for no reason when viewing video clips showing faces with pain expressions receiving needle penetration or faces with neutral expressions receiving a cotton swab touch. Experiment 1 found that participants pressed a button with greater response force when watching painful than non-painful stimuli. Participants who reported greater unpleasant feelings pressed the button harder when viewing painful stimuli. Experiment 2 revealed that passively viewing painful vs non-painful stimuli increased blood-oxygen-level-dependent signals in the middle cingulate cortex, supplementary motor cortex, and bilateral second somatosensory and inferior frontal cortex, which, however, were reduced by the action of button press without altruistic effects. In addition, individuals who reported higher personal distress illustrated greater decrease of the second somatosensory activity induced by button press. Our results indicate that empathy for pain motivates simple actions without altruistic effects that in turn reduce neural responses to others' pain, suggesting a functional role of action execution in self distress relief when viewing others' suffering.
共情被认为是利他行为的一种近因机制。我们研究了对疼痛的共情是否会驱动无利他效应的行为，以及此类行为如何调节对他人疼痛的神经反应。在两项实验中，我们要求健康成年人在观看视频片段时无故按下按钮，视频片段展示了面部带有疼痛表情的人接受针刺，或面部带有中性表情的人接受棉签触碰。实验1发现，与观看无疼痛刺激的视频相比，参与者在观看疼痛刺激视频时按下按钮的反应力度更大。报告有更强烈不愉快感受的参与者在观看疼痛刺激视频时按下按钮的力度更大。实验2表明，被动观看疼痛刺激与无疼痛刺激的视频相比，会增加扣带中央回、辅助运动皮层以及双侧第二体感皮层和额下回的血氧水平依赖信号，然而，在无利他效应的按下按钮行为作用下，这些信号会减弱。此外，报告有更高个人痛苦感的个体在按钮按下行为诱发的第二体感活动中表现出更大程度的下降。我们的研究结果表明，对疼痛的共情会激发无利他效应的简单行为，而这些行为反过来会减少对他人疼痛的神经反应，这表明在目睹他人受苦时，行为执行在减轻自身痛苦方面具有功能性作用。
