Cheng Joshua C, Anzolin Alessandra, Berry Michael, Honari Hamed, Paschali Myrella, Lazaridou Asimina, Lee Jeungchan, Ellingsen Dan-Mikael, Loggia Marco L, Grahl Arvina, Lindquist Martin A, Edwards Robert R, Napadow Vitaly
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, and Harvard Medical School, Charlestown, Massachusetts.
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Spaulding Rehabilitation Network, and Harvard Medical School, Charlestown, Massachusetts.
Arthritis Rheumatol. 2022 Apr;74(4):700-710. doi: 10.1002/art.42013. Epub 2022 Mar 10.
Abnormal central pain processing is a leading cause of pain in fibromyalgia (FM) and is perceptually characterized with the psychophysical measure of temporal summation of pain (TSP). TSP is the perception of increasingly greater pain in response to repetitive or tonic noxious stimuli. Previous neuroimaging studies have used static (i.e., summary) measures to examine the functional magnetic resonance imaging (fMRI) correlates of TSP in FM. However, functional brain activity rapidly and dynamically reorganizes over time, and, similarly, TSP is a temporally evolving process. This study was undertaken to demonstrate how a complete understanding of the neural circuitry supporting TSP in FM thus requires a dynamic measure that evolves over time.
We utilized novel methods for analyzing dynamic functional brain connectivity in patients with FM in order to examine how TSP-associated fluctuations are linked to the dynamic functional reconfiguration of the brain. In 84 FM patients and age- and sex-matched healthy controls, we collected high-temporal-resolution fMRI data during a resting state and during a state in which sustained cuff pressure pain was applied to the leg.
FM patients experienced greater TSP than healthy controls (mean ± SD TSP score 17.93 ± 19.24 in FM patients versus 9.47 ± 14.06 in healthy controls; P = 0.028), but TSP scores varied substantially between patients. In the brain, the presence versus absence of TSP in patients with FM was marked by more sustained enmeshment between sensorimotor and salience networks during the pain period. Furthermore, dynamic enmeshment was noted solely in FM patients with high TSP, as interactions with all other brain networks were dampened during the pain period.
This study elucidates the dynamic brain processes underlying facilitated central pain processing in FM. Our findings will enable future investigation of dynamic symptoms in FM.
中枢疼痛处理异常是纤维肌痛（FM）疼痛的主要原因，其在感知上的特征是通过疼痛时间总和（TSP）这一心理物理学测量方法来体现。TSP是指对重复性或持续性有害刺激产生的越来越强烈的疼痛感知。以往的神经影像学研究使用静态（即汇总）测量方法来检查FM中TSP与功能磁共振成像（fMRI）的相关性。然而，大脑功能活动会随着时间快速且动态地重新组织，同样，TSP也是一个随时间演变的过程。本研究旨在证明，要全面理解支持FM中TSP的神经回路，就需要一种随时间演变的动态测量方法。
我们采用了新的方法来分析FM患者的动态脑功能连接，以研究与TSP相关的波动如何与大脑的动态功能重构相联系。在84名FM患者以及年龄和性别匹配的健康对照者中，我们在静息状态和对腿部施加持续袖带压力疼痛的状态下收集了高时间分辨率的fMRI数据。
FM患者的TSP比健康对照者更强烈（FM患者的平均±标准差TSP评分为17.93±19.24，而健康对照者为9.47±14.06；P = 0.028），但患者之间的TSP评分差异很大。在大脑中，FM患者在疼痛期间感觉运动网络和突显网络之间更持续的相互联系标志着TSP的存在与否。此外，仅在TSP较高的FM患者中观察到动态相互联系，因为在疼痛期间与所有其他脑网络的相互作用减弱。
本研究阐明了FM中中枢疼痛处理易化的动态脑过程。我们的发现将有助于未来对FM动态症状的研究。
