Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel.
Medical Faculty Mannheim, Institute of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Heidelberg University, Heidelberg, Germany.
PLoS One. 2022 Apr 20;17(4):e0267170. doi: 10.1371/journal.pone.0267170. eCollection 2022.
The representation of variability in sensitivity to pain by differences in neural connectivity patterns and its association with psychological factors needs further investigation. This study assessed differences in resting-state functional connectivity (rsFC) and its association to cognitive-affective aspects of pain in two groups of healthy subjects with low versus high sensitivity to pain (LSP vs. HSP). We hypothesized that HSP will show stronger connectivity in brain regions involved in the affective-motivational processing of pain and that this higher connectivity would be related to negative affective and cognitive evaluations of pain.
Forty-eight healthy subjects were allocated to two groups according to their tolerability to cold stimulation (cold pressor test, CPT, 1°C). Group LSP (N = 24) reached the cut-off time of 180±0 sec and group HSP tolerated the CPT for an average of 13±4.8 sec. Heat, cold and mechanical evoked pain were measured, as well as pain-catastrophizing (PCS), depression, anxiety and stress (DASS-21). All subjects underwent resting state fMRI. ROI-to-ROI analysis was performed.
In comparison to the LSP, the HSP had stronger interhemispheric connectivity of the amygdala (p = 0.01) and between the amygdala and nucleus accumbens (NAc) (p = 0.01). Amygdala connectivity was associated with higher pain catastrophizing in the HSP only (p<0.01).
These findings suggest that high sensitivity to pain may be reflected by neural circuits involved in affective and motivational aspects of pain. To what extent this connectivity within limbic brain structures relates to higher alertness and more profound withdrawal behavior to aversive events needs to be further investigated.
通过神经连接模式的差异来表现对疼痛的敏感性的可变性及其与心理因素的关联需要进一步研究。本研究评估了两组健康受试者（低疼痛敏感性组[LSP]和高疼痛敏感性组[HSP]）静息状态功能连接（rsFC）的差异及其与疼痛的认知-情感方面的关系。我们假设 HSP 在涉及疼痛的情感-动机处理的大脑区域中表现出更强的连接，并且这种更高的连接与疼痛的负性情感和认知评估有关。
根据对冷刺激（冷加压试验，CPT，1°C）的耐受情况，将 48 名健康受试者分为两组。LSP 组（N=24）达到 180±0 秒的截止时间，HSP 组平均耐受 CPT 时间为 13±4.8 秒。测量了热、冷和机械诱发疼痛，以及疼痛灾难化（PCS）、抑郁、焦虑和压力（DASS-21）。所有受试者均进行静息态 fMRI 检查。进行了 ROI-ROI 分析。
与 LSP 相比，HSP 的杏仁核的半球间连接更强（p=0.01），杏仁核和伏隔核（NAc）之间的连接也更强（p=0.01）。只有 HSP 的杏仁核连接与更高的疼痛灾难化有关（p<0.01）。
这些发现表明，对疼痛的高度敏感可能反映了涉及疼痛的情感和动机方面的神经回路。这些边缘脑结构内的连接在多大程度上与对不愉快事件的更高警觉性和更深刻的回避行为有关，需要进一步研究。
