Aberrant topographical organization of the default mode network underlying the cognitive impairment of remitted late-onset depression
Aberrant topographical organization of the default mode network underlying the cognitive impairment of remitted late-onset depression
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缓解迟发性抑郁症认知障碍背后的默认模式网络的异常拓扑组织
DOI：
10.1016/j.neulet.2016.06.048
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发表时间：
2016
影响因子：
2.5
通讯作者：
Yuan Yonggui
中科院分区：
文献类型：
--
作者：
Yin Yingying;Wang Zan;Zhang Zhijun;Yuan Yonggui
探讨缓解型晚发抑郁症(RLOD)患者静息状态功能连接性(FC)和默认模式网络(DMN)拓扑结构的改变及其在认知功能损害中的作用。33名RLOD患者和31名健康对照接受了临床和认知评估以及静息状态功能磁共振成像(R-fMRI)扫描。通过对DMN区域的Pearson相关度量进行阈值处理，构建了FC网络，并用图论方法分析了其拓扑性质。非参数置换检验进一步用于拓扑度量值的分组比较。最后，运用多元线性回归分析来检验网络测量与认知绩效之间的关系。与健康对照组相比，患者普遍表现出DMN的FC降低和DMN的全局拓扑结构异常(即特征路径长度Lp增加和全局效率降低Eglob)。根据距离依赖的FC结果，长距离连接主要涉及前、后中枢之间的连接，短距离连接主要位于额叶。RLOD患者的全局拓扑结构与情景记忆成绩之间存在显著相关性。综上所述，本研究表明DMN的拓扑结构紊乱可能被认为是rLOD患者情景记忆缺陷的一个潜在的生物标志物。
To investigate the alteration of resting-state functional connectivity (FC) and topological organization of the default mode network (DMN), and their contribution to the cognitive impairment in remitted late-onset depression (rLOD) patients. Thirty-three rLOD patients and thirty-one healthy controls underwent clinical and cognitive evaluations as well as resting-state functional magnetic resonance imaging (R-fMRI) scans. The FC networks were constructed by thresholding Pearson correlation metrics of the DMN regions, and their topological properties were analyzed using graph theory-based approaches. Nonparametric permutation tests were further used for group comparisons of topological metrics. Finally, multiple linear regression analyses were performed to examine the relationships between the network measures and cognitive performances. Patients displayed universally decreased FC of DMN and abnormal global topology of the DMN (i.e., increased characteristic path lengthLpand reduced global efficiencyEglob) compared with healthy controls. According to the distance-dependent FC results, the long-distance connections were mainly involved in the connectivity between anterior and posterior hubs, and the short-distance connections were primarily located in the frontal lobe. There were significant correlations between the global topology and the episodic memory performance in rLOD patients. In conclusion, the present study indicated that the disrupted topological organization of the DMN might be considered as a potential biomarker of the episodic memory deficits in rLOD patients.