Department of Neurobiology and Behavior, University of California Irvine, Irvine, USA.
Department of Otolaryngology-Head and Neck Surgery, University of California Irvine, Irvine, USA.
Sci Rep. 2023 Feb 27;13(1):3333. doi: 10.1038/s41598-023-29280-x.
According to the facial feedback hypothesis, when we see an angry or happy face, we contract or flex the relevant muscles to recreate the expression to assist in identifying and experiencing the emotion reflected. We investigated the facial feedback hypothesis by using botulinum toxin type A (onabotulinumtoxinA; onabotA) injections to induce temporary paralysis in the glabellar muscles (responsible for frowning) and measured functional brain activity during the processing of emotional faces. Ten females viewed pictures of happy and angry faces during two functional magnetic resonance imaging (fMRI) scan sessions: one prior (Pre) to onabotA and one following (Active) onabotA injections. We found Pre vs. Active onabotA modulation of activity in the amygdala for both happy and angry faces, as well as modulation of activity in the fusiform gyrus for happy faces. Consistent with our predictions, preventing frowning through inhibition of glabellar muscle contraction altered amygdala processing for emotional faces. The modulation of amygdala and fusiform gyrus activity following onabotA may reflect compensatory processes in a neuroanatomical circuit involved in emotional processing that is engaged when facial feedback is impaired. These data contribute to a growing literature suggesting that inhibition of glabellar muscle contraction alters neural activity for emotional processing.Clinical Trials.gov registration number: NCT03373162.
根据面部反馈假说，当我们看到愤怒或快乐的面孔时，我们会收缩或伸展相关的肌肉来重现表情，以帮助识别和体验所反映的情绪。我们通过使用肉毒杆菌毒素 A（肉毒毒素 A；onabotA）注射来诱导皱眉肌（负责皱眉）暂时瘫痪，并在处理情绪面孔时测量功能大脑活动，从而研究了面部反馈假说。10 名女性在两次功能磁共振成像（fMRI）扫描期间观看了快乐和愤怒面孔的图片：一次是在肉毒毒素 A 注射前（Pre），一次是在肉毒毒素 A 注射后（Active）。我们发现 Pre 与 Active 肉毒毒素 A 对快乐和愤怒面孔的杏仁核活动都有调节作用，对快乐面孔的梭状回活动也有调节作用。与我们的预测一致，通过抑制皱眉肌收缩来防止皱眉改变了对情绪面孔的杏仁核处理。肉毒毒素 A 注射后杏仁核和梭状回活动的调节可能反映了情感处理中涉及的神经解剖回路的代偿过程，当面部反馈受损时，该回路就会被激活。这些数据有助于越来越多的文献表明，抑制皱眉肌收缩会改变情绪处理的神经活动。临床试验.gov 注册号：NCT03373162。
