Nelson Eric A, White David M, Kraguljac Nina V, Lahti Adrienne C
Department of Psychology, University of Alabama at Birmingham, Birmingham, AL, United States.
Department of Psychiatry, University of Alabama at Birmingham, Birmingham, AL, United States.
Front Psychiatry. 2018 Dec 20;9:699. doi: 10.3389/fpsyt.2018.00699. eCollection 2018.
Schizophrenia (SZ) is a d isease characterized by brain dysconnectivity and abnormal brain development. The study of cortical gyrification in schizophrenia may capture underlying alterations reflective of neurodevelopmental abnormalities more accurately than other imaging modalities. Graph-based connectomic approaches have been previously used in schizophrenia to study structural and functional brain covariance using a diversity of techniques. The goal of the present study was to evaluate morphological covariance using a measure of local gyrification index in patients with schizophrenia. The aims of this study were two-fold: (1) Evaluate the structural covariance of local gyrification index using graph theory measures of integration and segregation in unmedicated patients with schizophrenia compared to healthy controls and (2) investigate changes in these measures following a short antipsychotic drug (APD) treatment. Using a longitudinal prospective design, structural scans were obtained prior to treatment in 34 unmedicated patients with SZ and after 6 weeks of treatment with risperidone. To control for the effect of time, 23 matched healthy controls (HC) were also scanned twice, 6 weeks apart. The cortical surface of each structural image was reconstructed and local gyrification index values were computed using FreeSurfer. Local gyrification index values where then parcellated into atlas based regions and entered into a 68 × 68 correlation matrix to construct local gyrification index connectomes for each group at each time point. Longitudinal comparisons showed significant group by time interactions for measures of segregation (clustering, local efficiency) and modularity, but not for measures of integration (path length, global efficiency). tests showed increased clustering, local efficiency, and modularity connectomes in unmedicated patients with SZ at baseline compared to HC. tests did not show significant within group differences for HCs or patients with SZ. After 6 weeks of treatment, there were no significant differences between the groups on these measures. Abnormal cortical topography is detected in schizophrenia and is modified by short term APD treatment reflective of decreases in hyper-specialization in network connectivity. We speculate that changes in the structural organization of the brain is achieved through the neuroplastic effects that APDs have on brain tissue, thus promoting more efficient brain connections and, possibly, a therapeutic effect.
精神分裂症（SZ）是一种以大脑连接功能障碍和大脑发育异常为特征的疾病。与其他成像方式相比，对精神分裂症患者大脑脑回形成的研究可能更准确地捕捉到反映神经发育异常的潜在改变。基于图谱的连接组学方法此前已被用于精神分裂症研究，以使用多种技术研究大脑结构和功能的协方差。本研究的目的是使用局部脑回形成指数来评估精神分裂症患者的形态协方差。本研究的目的有两个：（1）与健康对照相比，使用整合和分离的图谱理论测量方法评估未用药的精神分裂症患者局部脑回形成指数的结构协方差；（2）研究短期抗精神病药物（APD）治疗后这些测量指标的变化。采用纵向前瞻性设计，在34例未用药的SZ患者治疗前和使用利培酮治疗6周后进行结构扫描。为了控制时间的影响，还对23名匹配的健康对照（HC）进行了两次扫描，间隔6周。使用FreeSurfer重建每个结构图像的皮质表面并计算局部脑回形成指数值。然后将局部脑回形成指数值划分为基于图谱的区域，并输入到一个68×68的相关矩阵中，以构建每个组在每个时间点的局部脑回形成指数连接组。纵向比较显示，在分离测量指标（聚类、局部效率）和模块性方面存在显著的组×时间交互作用，但在整合测量指标（路径长度、全局效率）方面不存在。检验显示，与HC相比，未用药的SZ患者在基线时聚类、局部效率和模块性连接组增加。检验未显示HC组或SZ患者组内有显著差异。治疗6周后，两组在这些测量指标上没有显著差异。在精神分裂症中检测到异常的皮质拓扑结构，并且短期APD治疗可对其进行改变，这反映了网络连接中超专业化程度的降低。我们推测，大脑结构组织的变化是通过APD对脑组织的神经可塑性作用实现 的，从而促进更有效的大脑连接，并可能产生治疗效果。
