Ryu Jihye, Kao Jonathan C, Bari Ausaf
Department of Neurosurgery, David Geffen School of Medicine at the University of California Los Angeles, Los Angeles, CA, United States.
Department of Electrical and Computer Engineering, University of California Los Angeles, Los Angeles, CA, United States.
Pain. 2025 Mar 20;166(9):e261-e275. doi: 10.1097/j.pain.0000000000003592.
Chronic pain is characterized by spontaneous fluctuations in pain intensity, a phenomenon that remains poorly understood. The aim of this study is to elucidate the neural mechanisms underlying pain fluctuations in patients with chronic pain undergoing deep brain stimulation surgery. We recorded local field potentials (LFPs) from pain-processing hub structures, including the ventral posteromedial nucleus of the thalamus, subgenual cingulate cortex, and periventricular and periaqueductal gray, while patients continuously reported their pain levels. Using novel auto-mutual information metrics to analyze LFP stochastic patterns, we found that pain intensity correlated with both increased regularity of spike-like events and greater past-dependency of neural oscillations in the 4- to 15-Hz frequency band. In addition, during periods of higher pain states, we observed enhanced functional connectivity between the examined hub structures and the prefrontal cortex, suggesting a more focused flow of pain-related information within the pain circuit. By characterizing the dynamic nature of pain fluctuations, this study bridges the gap in understanding moment-to-moment pain variations and their underlying neural mechanisms, paving the way for improved chronic pain management strategies.
慢性疼痛的特点是疼痛强度会自发波动，这一现象目前仍知之甚少。本研究旨在阐明接受深部脑刺激手术的慢性疼痛患者疼痛波动背后的神经机制。我们记录了来自疼痛处理枢纽结构的局部场电位（LFP），包括丘脑腹后内侧核、膝下扣带回皮质以及脑室周围和导水管周围灰质，同时患者持续报告他们的疼痛程度。使用新颖的自互信息指标来分析LFP随机模式，我们发现疼痛强度与尖峰样事件的规律性增加以及4至15赫兹频段神经振荡的更强过去依赖性均相关。此外，在疼痛状态较高的时期，我们观察到所检查的枢纽结构与前额叶皮质之间的功能连接增强，这表明疼痛回路内与疼痛相关的信息流更加集中。通过描述疼痛波动的动态性质，本研究填补了理解瞬间疼痛变化及其潜在神经机制方面的空白，为改进慢性疼痛管理策略铺平了道路。
