Guo Wenbin, Liu Feng, Liu Jianrong, Yu Liuyu, Zhang Jian, Zhang Zhikun, Xiao Changqing, Zhai Jinguo, Zhao Jingping
Mental Health Center, the First Affiliated Hospital, Guangxi Medical University, Nanning, China;
Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, Sichuan, China;
Schizophr Bull. 2015 Jan;41(1):57-65. doi: 10.1093/schbul/sbu126. Epub 2014 Aug 28.
Anatomical deficits and resting-state functional connectivity (FC) alterations in prefrontal-thalamic-cerebellar circuit have been implicated in the neurobiology of schizophrenia. However, the effect of structural deficits in schizophrenia on causal connectivity of this circuit remains unclear. This study was conducted to examine the causal connectivity biased by structural deficits in first-episode, drug-naive schizophrenia patients. Structural and resting-state functional magnetic resonance imaging (fMRI) data were obtained from 49 first-episode, drug-naive schizophrenia patients and 50 healthy controls. Data were analyzed by voxel-based morphometry and Granger causality analysis. The causal connectivity of the integrated prefrontal-thalamic (limbic)-cerebellar (sensorimotor) circuit was partly affected by structural deficits in first-episode, drug-naive schizophrenia as follows: (1) unilateral prefrontal-sensorimotor connectivity abnormalities (increased driving effect from the left medial prefrontal cortex [MPFC] to the sensorimotor regions); (2) bilateral limbic-sensorimotor connectivity abnormalities (increased driving effect from the right anterior cingulate cortex [ACC] to the sensorimotor regions and decreased feedback from the sensorimotor regions to the right ACC); and (3) bilateral increased and decreased causal connectivities among the sensorimotor regions. Some correlations between the gray matter volume of the seeds, along with their causal effects and clinical variables (duration of untreated psychosis and symptom severity), were also observed in the patients. The findings indicated the partial effects of structural deficits in first-episode, drug-naive schizophrenia on the prefrontal-thalamic (limbic)-cerebellar (sensorimotor) circuit. Schizophrenia may reinforce the driving connectivities from the left MPFC or right ACC to the sensorimotor regions and may disrupt bilateral causal connectivities among the sensorimotor regions.
前额叶 - 丘脑 - 小脑回路的解剖学缺陷和静息态功能连接(FC)改变与精神分裂症的神经生物学有关。然而,精神分裂症中结构缺陷对该回路因果连接的影响仍不清楚。本研究旨在检查首发、未用药的精神分裂症患者结构缺陷所导致的因果连接。从49名首发、未用药的精神分裂症患者和50名健康对照者获取了结构和静息态功能磁共振成像(fMRI)数据。通过基于体素的形态学测量和格兰杰因果分析对数据进行分析。首发、未用药的精神分裂症患者的结构缺陷部分影响了前额叶 - 丘脑(边缘系统) - 小脑(感觉运动)整合回路的因果连接,具体如下:(1)单侧前额叶 - 感觉运动连接异常(从左侧内侧前额叶皮质[MPFC]到感觉运动区域的驱动效应增加);(2)双侧边缘系统 - 感觉运动连接异常(从右侧前扣带回皮质[ACC]到感觉运动区域的驱动效应增加以及从感觉运动区域到右侧ACC的反馈减少);(3)感觉运动区域之间双侧因果连接的增加和减少。在患者中还观察到种子灰质体积与其因果效应和临床变量(未治疗精神病的持续时间和症状严重程度)之间的一些相关性。研究结果表明首发、未用药的精神分裂症患者的结构缺陷对前额叶 - 丘脑(边缘系统) - 小脑(感觉运动)回路有部分影响。精神分裂症可能增强从左侧MPFC或右侧ACC到感觉运动区域的驱动连接,并可能破坏感觉运动区域之间的双侧因果连接。