School of Psychology, Shenzhen University, Shenzhen, China.
Shenzhen Key Laboratory of Affective and Social Cognitive Science, Shenzhen University, Shenzhen, China.
Neural Plast. 2019 Jul 9;2019:2687150. doi: 10.1155/2019/2687150. eCollection 2019.
Patients with somatoform pain disorder (SPD) suffer from somatic pain that cannot be fully explained by specific somatic pathology. While the pain experience requires the integration of sensory and contextual processes, the cortical oscillations have been suggested to play a crucial role in pain processing and integration. The present study is aimed at identifying the abnormalities of spontaneous cortical oscillations among patients with SPD, thus for a better understanding of the ongoing brain states in these patients. Spontaneous electroencephalography data during a resting state with eyes open were recorded from SPD patients and healthy controls, and their cortical oscillations as well as functional connectivity were compared using both electrode-level and source-level analysis. Compared with healthy controls, SPD patients exhibited greater resting-state alpha oscillations (8.5-12.5 Hz) at the parietal region, as reflected by both electrode-level spectral power density and exact low-resolution brain electromagnetic tomography (eLORETA) cortical current density. A significant correlation between parietal alpha oscillation and somatization severity was observed in SPD patients, after accounting for the influence of anxiety and depression. Functional connectivity analysis further revealed a greater frontoparietal connectivity of the resting-state alpha oscillations in SPD patients, which was indexed by the coherence between pairs of electrodes and the linear connectivity between pairs of eLORETA cortical sources. The enhanced resting-state alpha oscillation in SPD patients could be relevant with attenuated sensory information gating and excessive integration of pain-related information, while the enhanced frontoparietal connectivity could be reflecting their sustained attention to bodily sensations and hypervigilance to somatic sensations.
躯体形式疼痛障碍（SPD）患者患有无法通过特定躯体病理学充分解释的躯体疼痛。虽然疼痛体验需要感觉和上下文过程的整合，但皮质振荡被认为在疼痛处理和整合中起着关键作用。本研究旨在确定 SPD 患者自发皮质振荡的异常，从而更好地了解这些患者的大脑状态。使用电极级和源级分析，从 SPD 患者和健康对照者在睁眼静息状态下记录自发脑电图数据，并比较其皮质振荡和功能连接。与健康对照组相比，SPD 患者在顶叶区域表现出更大的静息状态 alpha 振荡（8.5-12.5Hz），这反映在电极级频谱功率密度和精确低分辨率脑电磁断层扫描（eLORETA）皮质电流密度上。在考虑焦虑和抑郁的影响后，在 SPD 患者中观察到顶叶 alpha 振荡与躯体化严重程度之间存在显著相关性。功能连接分析进一步显示，SPD 患者静息状态 alpha 振荡的额顶连接增强，这由电极对之间的相干性和 eLORETA 皮质源对之间的线性连接来表示。SPD 患者静息状态 alpha 振荡增强可能与感觉信息门控减弱和疼痛相关信息过度整合有关，而额顶连接增强可能反映了他们对身体感觉的持续关注和对躯体感觉的过度警惕。
