Department of Neuroscience, University of Sheffield, Sheffield, UK.
Department of Clinical Medical Sciences, Psychiatry Unit, University of the West Indies, St. Augustine Campus, Trinidad and Tobago.
J Neurol Sci. 2021 Mar 15;422:117326. doi: 10.1016/j.jns.2021.117326. Epub 2021 Jan 22.
A common symptom of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is post-exertional malaise (PEM). Various brain abnormalities have been observed in patients with ME/CFS, especially in insular and limbic areas, but their link with ME/CFS symptoms is still unclear. This pilot study aimed at investigating the association between PEM in ME/CFS and changes in functional connectivity (FC) of two main networks: the salience network (SN) and the default-mode network (DMN).
A total of 16 women, 6 with and 10 without ME/CFS, underwent clinical and MRI assessment before and after cognitive exertion. Resting-state FC maps of 7 seeds (3 for the SN and 4 for the DMN) and clinical measures of fatigue, pain and cognition were analysed with repeated-measure models. FC-symptom change associations were also investigated.
Exertion induced increases in fatigue and pain in patients with ME/CFS compared to the control group, while no changes were found in cognitive performance. At baseline, patients showed altered FC between some DMN seeds and frontal areas and stronger FC between all SN seeds and left temporal areas and the medulla. Significantly higher FC increases in patients than in controls were found only between the right insular seed and frontal and subcortical areas; these increases correlated with worsening of symptoms.
Cognitive exertion can induce worsening of ME/CFS-related symptoms. These changes were here associated with strengthening of FC of the right insula with areas involved in reward processing and cognitive control.
肌痛性脑脊髓炎/慢性疲劳综合征（ME/CFS）的常见症状是活动后不适（PEM）。患有 ME/CFS 的患者的大脑出现各种异常，特别是在岛叶和边缘区域，但它们与 ME/CFS 症状的联系仍不清楚。这项初步研究旨在调查 ME/CFS 中 PEM 与两个主要网络的功能连接（FC）变化之间的关联：显着性网络（SN）和默认模式网络（DMN）。
总共 16 名女性，其中 6 名患有 ME/CFS，10 名无 ME/CFS，在认知用力前后进行了临床和 MRI 评估。使用重复测量模型分析了 7 个种子（3 个用于 SN，4 个用于 DMN）的静息状态 FC 图和疲劳、疼痛和认知的临床测量值，并研究了 FC-症状变化的关联。
与对照组相比，ME/CFS 患者的用力会导致疲劳和疼痛增加，而认知表现没有变化。在基线时，患者显示出一些 DMN 种子与额叶区域之间的 FC 改变，以及所有 SN 种子与左侧颞叶区域和延髓之间的 FC 更强。仅在右侧岛叶种子与额叶和皮质下区域之间发现患者的 FC 增加明显高于对照组；这些增加与症状恶化相关。
认知用力会导致 ME/CFS 相关症状恶化。这些变化与右岛叶与参与奖励处理和认知控制的区域的 FC 增强有关。
