Kornelsen Jennifer, McIver Theresa A, Stroman Patrick W
Department of Radiology, University of Manitoba, SR226 Kleysen Institute for Advanced Medicine, 710 William Avenue, Winnipeg MB, R2H 2A6, Canada, Phone: +1 204 787-5658, Fax: +1 204 233-2777.
Queen's University, Centre for Neuroscience Studies, Kingston, Ontario, Canada.
Scand J Pain. 2019 Jul 26;19(3):583-596. doi: 10.1515/sjpain-2018-0341.
Background and aims Research has shown that negative emotions increase perceived pain whereas positive emotions reduce pain. Here we aim to investigate the neural mechanisms underlying this phenomenon. Methods While undergoing functional magnetic resonance imaging of the brain, 20 healthy adult females were presented with negative, neutral, and positive emotion-evoking visual stimuli in combination with the presentation of a noxious thermal stimulus to the hand. Participants rated the intensity and unpleasantness of the noxious thermal stimulus during each of the valence conditions. General linear model analyses were performed on the imaging data for each valence condition and specific contrasts were run. Results Significant differences were detected for the emotional modulation of pain (EMP) between the positive and negative conditions. Unique to the positive condition, there was increased activity in the inferior parietal, parahippocampal/perirhinal, precuneus/superior parietal, and the prefrontal cortices. Unique to the negative condition, there was increased activity in anterior and posterior cingulate and angular gyrus. Conclusions Positive and negative EMP appear to involve different brain regions. Implications Although there is some overlap in the brain regions involved in the positive and negative EMP, brain regions unique to each condition are identified and, moreover, the regions identified are involved in internal and external focus, respectively, pointing to a potential mechanism underlying this phenomenon.
背景与目的 研究表明，负面情绪会增加痛感，而正面情绪则会减轻疼痛。在此，我们旨在探究这一现象背后的神经机制。方法 20名健康成年女性在接受脑部功能磁共振成像时，会看到引发负面、中性和正面情绪的视觉刺激，同时手部会受到有害热刺激。参与者在每种效价条件下对有害热刺激的强度和不适感进行评分。对每种效价条件下的成像数据进行一般线性模型分析，并进行特定对比。结果 在正面和负面条件之间检测到疼痛的情绪调节（EMP）存在显著差异。在正面条件下，独特的是，顶下小叶、海马旁/嗅周皮质、楔前叶/顶上小叶和前额叶皮质的活动增加。在负面条件下，独特的是，前扣带回和后扣带回以及角回的活动增加。结论 正面和负面的EMP似乎涉及不同的脑区。意义 尽管正面和负面EMP所涉及的脑区存在一些重叠，但每种条件下独特的脑区已被识别，此外，所识别的区域分别涉及内部和外部关注点，这指出了这一现象背后的潜在机制。
