Iwase Masao, Ouchi Yasuomi, Okada Hiroyuki, Yokoyama Chihiro, Nobezawa Shuji, Yoshikawa Etsuji, Tsukada Hideo, Takeda Masaki, Yamashita Ko, Takeda Masatoshi, Yamaguti Kouzi, Kuratsune Hirohiko, Shimizu Akira, Watanabe Yasuyoshi
Psychiatry, and Department of Clinical Neuroscience, Osaka University Graduate School of Medicine, Suita-shi, Osaka 565-0871, Japan.
Neuroimage. 2002 Oct;17(2):758-68.
Laughter or smile is one of the emotional expressions of pleasantness with characteristic contraction of the facial muscles, of which the neural substrate remains to be explored. This currently described study is the first to investigate the generation of human facial expression of pleasant emotion using positron emission tomography and H(2)(15)O. Regional cerebral blood flow (rCBF) during laughter/smile induced by visual comics and the magnitude of laughter/smile indicated significant correlation in the bilateral supplementary motor area (SMA) and left putamen (P < 0.05, corrected), but no correlation in the primary motor area (M1). In the voluntary facial movement, significant correlation between rCBF and the magnitude of EMG was found in the face area of bilateral M1 and the SMA (P < 0.001, uncorrected). Laughter/smile, as opposed to voluntary movement, activated the visual association areas, left anterior temporal cortex, left uncus, and orbitofrontal and medial prefrontal cortices (P < 0.05, corrected), whereas voluntary facial movement generated by mimicking a laughing/smiling face activated the face area of the left M1 and bilateral SMA, compared with laughter/smile (P < 0.05, corrected). We demonstrated distinct neural substrates of emotional and volitional facial expression and defined cognitive and experiential processes of a pleasant emotion, laughter/smile.
笑或微笑是一种愉快的情感表达方式，其特征是面部肌肉收缩，而其神经基础仍有待探索。目前所描述的这项研究是首次使用正电子发射断层扫描和H(2)(15)O来研究人类愉快情绪面部表情的产生。在视觉漫画引发的笑/微笑过程中的局部脑血流(rCBF)以及笑/微笑的程度，在双侧辅助运动区(SMA)和左侧壳核中显示出显著相关性(P < 0.05，校正后)，但在初级运动区(M1)中无相关性。在随意面部运动中，在双侧M1的面部区域和SMA中发现rCBF与肌电图幅度之间存在显著相关性(P < 0.001，未校正)。与随意运动相反，笑/微笑激活了视觉联合区、左侧颞前叶皮质、左侧钩回以及眶额皮质和内侧前额叶皮质(P < 0.05，校正后)，而模仿笑/微笑的脸产生的随意面部运动与笑/微笑相比，激活了左侧M1的面部区域和双侧SMA(P < 0.05，校正后)。我们证明了情感性和意志性面部表情的不同神经基础，并定义了愉快情绪、笑/微笑的认知和体验过程。
