Will Mara, Stroman Patrick W
Centre for Neuroscience Studies, Queen's University, Kingston, ON K7L 3N6, Canada.
Brain Sci. 2025 Jun 4;15(6):603. doi: 10.3390/brainsci15060603.
BACKGROUND/OBJECTIVES: Fibromyalgia (FM) is a chronic pain condition that includes symptoms of hyperalgesia and has an unknown etiology. This study aimed to further investigate the underlying neural signaling mechanisms and their relation to observed blood oxygenation-level dependent (BOLD) signal increases at the onset of functional magnetic resonance imaging (fMRI) runs.
The possible neural mechanisms were first explored by reviewing the current literature. The second component of this study involved a voxel-by-voxel analysis of BOLD responses in all regions of the brain. The fMRI data were obtained from a previous study of participants with and without fibromyalgia during fMRI runs involving either a noxious heat pain stimulus or no stimulus.
The literature review indicates that no single factor can explain the initial BOLD signal rise observed in FM but that there are likely multiple interacting influences. These include physiological dysregulation via mechanisms, such as oxidative stress, mitochondrial dysfunction, and cytokine activity, and may involve the sympathetic nervous system. The analysis of BOLD responses demonstrated that the initial BOLD rises occur specifically in gray matter regions and are largest in regions involved with pain processing, including the right insular cortex and periaqueductal gray region. Moreover, the BOLD rise is significantly larger in people with FM prior to the application of a noxious stimulus.
The initial rise in BOLD response demonstrates heightened metabolic demand that is exaggerated in people with FM. It appears to be influenced by cognitive factors such as anticipation and may reflect neural dysregulation, possibly involving autonomic signaling.
背景/目的：纤维肌痛（FM）是一种慢性疼痛疾病，包括痛觉过敏症状，其病因不明。本研究旨在进一步探究潜在的神经信号传导机制及其与功能磁共振成像（fMRI）扫描开始时观察到的血氧水平依赖（BOLD）信号增加之间的关系。
首先通过回顾当前文献来探索可能的神经机制。本研究的第二个部分涉及对大脑所有区域的BOLD反应进行逐体素分析。fMRI数据来自之前一项针对有和没有纤维肌痛的参与者的研究，该研究中的fMRI扫描涉及有害热痛刺激或无刺激。
文献综述表明，没有单一因素可以解释在FM中观察到的初始BOLD信号升高，但可能存在多种相互作用的影响。这些影响包括通过氧化应激、线粒体功能障碍和细胞因子活性等机制导致的生理失调，并且可能涉及交感神经系统。对BOLD反应的分析表明，初始BOLD升高 specifically发生在灰质区域，并且在与疼痛处理相关的区域中最大，包括右侧岛叶皮质和导水管周围灰质区域。此外，在施加有害刺激之前，FM患者的BOLD升高明显更大。
BOLD反应的初始升高表明代谢需求增加，这在FM患者中更为明显。它似乎受到预期等认知因素的影响，并且可能反映神经失调，可能涉及自主信号传导。
