Alves Rael Lopes, Zortea Maxciel, Serrano Paul Vicuña, Brugnera Tomedi Rafaela, Pereira de Almeida Rodrigo, Torres Iraci L S, Fregni Felipe, Caumo Wolnei
Post-Graduate Program in Medical Sciences, School of Medicine, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Brazil.
Laboratory of Pain and Neuromodulation, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, Brazil.
Front Neurosci. 2023 Nov 27;17:1233979. doi: 10.3389/fnins.2023.1233979. eCollection 2023.
Electroencephalography (EEG) has identified neural activity in specific brain regions as a potential indicator of the neural signature of chronic pain. This study compared the lagged coherence connectivity between regions of interest (ROIs) associated with the pain connectome in women with fibromyalgia (FM) and healthy women (HC).
We evaluated 64 participants (49 FM and 15 HC) during resting-state EEG sessions under both eyes open (EO) and eyes closed (EC) conditions. In addition to EEG measurements, we assessed clinical and psychological symptoms and serum levels of brain-derived neurotrophic factor (BDNF). The connectivity between eight ROIs was computed across eight different EEG frequencies.
The FM group demonstrated increased connectivity between the left dorsolateral prefrontal cortex (DLPFC) and right anterior cingulate cortex (ACC), specifically in the beta-3 frequency band ( = 3.441, = 0.044). When comparing the EO and EC conditions, FM patients exhibited heightened interhemispheric connectivity between insular areas ( = 3.372, = 0.024) and between the left insula (INS) and right DLPFC ( = 3.695, = 0.024) within the beta-3 frequency band. In the EC condition, there was a negative correlation between pain disability and connectivity in the beta-3 frequency band between the left ACC and the left primary somatosensory cortex (SI; = -0.442, = 0.043). In the EO condition, there was a negative correlation between central sensitization severity and lagged coherence connectivity in the alpha-2 frequency band between the right ACC and left SI ( = 0.428, = 0.014). Moreover, in the EO-EC comparison, the lagged coherence connection between the left DLPFC and right INS, indexed by the gamma frequency band, showed a negative correlation with serum BDNF levels ( = -0.506, = 0.012).
These findings indicate that increased connectivity between different pain processing circuits, particularly in the beta-3 frequency band during rest, may serve as neural biomarkers for the chronic pain brain signature associated with neuroplasticity and the severity of FM symptoms.
脑电图（EEG）已确定特定脑区的神经活动是慢性疼痛神经特征的潜在指标。本研究比较了纤维肌痛（FM）女性和健康女性（HC）中与疼痛连接组相关的感兴趣区域（ROI）之间的滞后相干连通性。
我们在双眼睁开（EO）和双眼闭合（EC）条件下的静息态EEG检查期间评估了64名参与者（49名FM患者和15名HC）。除了EEG测量外，我们还评估了临床和心理症状以及脑源性神经营养因子（BDNF）的血清水平。在八个不同的EEG频率上计算了八个ROI之间的连通性。
FM组在左侧背外侧前额叶皮质（DLPFC）和右侧前扣带回皮质（ACC）之间表现出增强的连通性，特别是在β-3频段（ = 3.441， = 0.044）。在比较EO和EC条件时，FM患者在β-3频段内岛叶区域之间（ = 3.372， = 0.024）以及左侧岛叶（INS）和右侧DLPFC之间（ = 3.695， = 0.024）表现出增强的半球间连通性。在EC条件下，疼痛残疾与左侧ACC和左侧初级体感皮层（SI）之间β-3频段的连通性呈负相关（ = -0.442， = 0.043）。在EO条件下，中枢敏化严重程度与右侧ACC和左侧SI之间α-2频段的滞后相干连通性呈负相关（ = 0.428， = 0.014）。此外，在EO - EC比较中，以γ频段为指标的左侧DLPFC和右侧INS之间的滞后相干连接与血清BDNF水平呈负相关（ = -0.506， = 0.012）。
这些发现表明，不同疼痛处理回路之间连通性的增加，特别是在静息时的β-3频段，可能作为与神经可塑性和FM症状严重程度相关的慢性疼痛脑特征的神经生物标志物。
