Department of Psychology, University of Konstanz, D-78457 Konstanz, Germany.
J Neurosci. 2013 Apr 3;33(14):6018-26. doi: 10.1523/JNEUROSCI.2763-12.2013.
Research has linked oscillatory activity in the α frequency range, particularly in sensorimotor cortex, to processing of social actions. Results further suggest involvement of sensorimotor α in the processing of facial expressions, including affect. The sensorimotor face area may be critical for perception of emotional face expression, but the role it plays is unclear. The present study sought to clarify how oscillatory brain activity contributes to or reflects processing of facial affect during changes in facial expression. Neuromagnetic oscillatory brain activity was monitored while 30 volunteers viewed videos of human faces that changed their expression from neutral to fearful, neutral, or happy expressions. Induced changes in α power during the different morphs, source analysis, and graph-theoretic metrics served to identify the role of α power modulation and cross-regional coupling by means of phase synchrony during facial affect recognition. Changes from neutral to emotional faces were associated with a 10-15 Hz power increase localized in bilateral sensorimotor areas, together with occipital power decrease, preceding reported emotional expression recognition. Graph-theoretic analysis revealed that, in the course of a trial, the balance between sensorimotor power increase and decrease was associated with decreased and increased transregional connectedness as measured by node degree. Results suggest that modulations in α power facilitate early registration, with sensorimotor cortex including the sensorimotor face area largely functionally decoupled and thereby protected from additional, disruptive input and that subsequent α power decrease together with increased connectedness of sensorimotor areas facilitates successful facial affect recognition.
研究将α频带的振荡活动，特别是感觉运动皮层中的活动，与社会动作的处理联系起来。结果进一步表明，感觉运动α参与了面部表情的处理，包括情感。感觉运动面部区域可能对面部表情的感知至关重要，但它的作用尚不清楚。本研究旨在阐明振荡脑活动如何有助于或反映面部表情变化过程中面部情感的处理。当 30 名志愿者观看人类面部表情从中性变为恐惧、中性或快乐表情的视频时，监测了神经磁振荡脑活动。在不同形态下的α功率变化、源分析和图论度量，用于通过相位同步识别面部情感识别过程中的α功率调制和跨区域耦合的作用。从中性到情感面孔的变化与 10-15 Hz 的功率增加有关，该功率增加定位于双侧感觉运动区，同时伴有枕部功率降低，先于报告的情感表达识别。图论分析表明，在试验过程中，传感器功率增加和减少之间的平衡与跨区域连接的减少和增加有关，这可以通过节点度来衡量。结果表明，α 功率的调制促进了早期的登记，感觉运动皮层包括感觉运动面部区域在功能上很大程度上被分离出来，从而免受额外的干扰输入，随后的α 功率下降和感觉运动区域之间连接的增加促进了成功的面部情感识别。
