Clinic for Psychiatry and Psychotherapy, University Hospital Leipzig, Germany; LIFE - Leipzig Research Centre for Civilization Diseases, University of Leipzig, Germany.
Clin Neurophysiol. 2013 Dec;124(12):2421-30. doi: 10.1016/j.clinph.2013.05.031. Epub 2013 Aug 19.
Functional magnetic resonance imaging (fMRI) studies found alterations of functional connectivity in obsessive compulsive disorder (OCD). However, there is little knowledge about region of interest (ROI) based electroencephalogram (EEG) connectivity, i.e. lagged non-linear and linear coherence in OCD. Goal of this study was to compare these EEG measures during rest and at different vigilance stages between patients and healthy controls (HC).
A 15 min resting-state EEG was recorded in 30 unmedicated patients and 30 matched HC. Intracortical lagged non-linear coherence of the main EEG-frequency bands within a set of frontal ROIs and within the default mode network (DMN) were computed and compared using intracortical exact low resolution electromagnetic tomography (eLORETA) software.
Lagged non-linear but not linear coherence was significantly decreased for patients in comparison to HC for the beta 2 frequency between frontal brain areas but not within the DMN. When analysing separate EEG-vigilance stages, only high vigilance stages yielded decreased frontal phase synchronisation at beta and theta frequencies.
The results underline an altered neuronal communication within frontal brain areas during rest in OCD.
These findings encourage further research on connectivity measures as possible biomarkers for physiological homogeneous subgroups.
功能磁共振成像（fMRI）研究发现强迫症（OCD）患者的功能连接存在改变。然而，关于基于感兴趣区域（ROI）的脑电图（EEG）连接，即 OCD 中的滞后非线性和线性相干性，我们知之甚少。本研究的目的是比较患者和健康对照组（HC）在休息和不同警觉阶段的这些 EEG 测量值。
对 30 名未接受药物治疗的患者和 30 名匹配的 HC 进行了 15 分钟的静息状态 EEG 记录。使用皮层内精确低分辨率电磁层析成像（eLORETA）软件计算并比较了一组额叶 ROI 内和默认模式网络（DMN）内主要 EEG 频带的皮层内滞后非线性相干性和线性相干性。
与 HC 相比，患者的滞后非线性相干性但不是线性相干性在额叶脑区的β2 频率下显著降低，但在 DMN 内则没有。当分析单独的 EEG 警觉阶段时，只有高警觉阶段在β和θ频率下表现出额叶相位同步性降低。
这些结果强调了 OCD 患者在休息时额叶脑区神经元通讯的改变。
这些发现鼓励进一步研究连接性测量，作为生理同质亚组的可能生物标志物。
