Department of Neurology and Centre of Clinical Neuroscience, First Faculty of Medicine and General University Hospital in Prague, Charles University, Czech Republic.
Max Planck Institute for Human Cognitive and Brain Sciences, Stephanstr. 1A, Leipzig 04103, Germany.
Neuropsychologia. 2018 Apr;112:105-115. doi: 10.1016/j.neuropsychologia.2018.03.011. Epub 2018 Mar 11.
Mild cognitive impairment (MCI) affects approximately one-third of non-demented Parkinson's Disease (PD) patients. We aimed at investigating the neural correlates of MCI in PD combining multimodal magnetic resonance imaging (MRI) with large-scale data from the literature. We analyzed 31 PD patients and 30 matched controls. The standard neuropsychological assessment of PD-MCI covered memory, attention, executive functions, language and visuospatial abilities. Following validated criteria, 16 patients were classified as showing MCI. Whole-brain functional connectivity and structural volume changes were assessed, respectively, by means of eigenvector centrality (EC) and voxel-based morphometry. To address the involvement of specific functional brain networks, we validated our results by building a meta-analytic co-activation map (MACM) based on the previous literature and then testing its overlap with the parcellation of functional networks derived from 1000 healthy controls. The EC comparison between PD with normal cognition and controls showed a selective decline in interconnectedness in the bilateral lentiform nuclei. Differently, comparing PD with MCI and controls revealed additional changes in non-motor areas. Directly comparing PD with and without MCI, we found a reduced interconnectedness in the bilateral superior parietal lobules and precuneus. No differences in brain volume were detected comparing these patient groups. The MACM and overlap analyses showed that the observed connectivity changes were localized in the hubs of the dorsal attention network. Notably, this aligned with the predominant attention deficit observed in our sample. Overall, functional impairment in the dorsal attention network seems to be the hallmark of MCI due to PD, thus extending previous findings of brain connectivity disruption in non-motor networks.
轻度认知障碍 (MCI) 影响约三分之一非痴呆帕金森病 (PD) 患者。我们旨在通过结合多模态磁共振成像 (MRI) 和来自文献的大规模数据，研究 PD 中 MCI 的神经相关性。我们分析了 31 名 PD 患者和 30 名匹配的对照者。PD-MCI 的标准神经心理学评估涵盖了记忆、注意力、执行功能、语言和视空间能力。根据验证标准，16 名患者被归类为 MCI。通过特征向量中心度 (EC) 和基于体素的形态计量学分别评估全脑功能连接和结构体积变化。为了研究特定功能脑网络的参与情况，我们根据先前的文献构建了一个元分析共激活图 (MACM)，并测试其与从 1000 名健康对照者中得出的功能网络分区的重叠，从而验证了我们的结果。PD 伴正常认知与对照组之间的 EC 比较显示，双侧豆状核的连通性选择性下降。相比之下，将 PD 伴 MCI 与对照组进行比较显示，非运动区有额外的变化。直接将 PD 伴 MCI 与不伴 MCI 进行比较，我们发现双侧顶叶上回和楔前叶的连通性降低。比较这些患者组时，未发现脑体积差异。MACM 和重叠分析表明，观察到的连接变化定位于背侧注意网络的枢纽。值得注意的是，这与我们样本中观察到的主要注意力缺陷相一致。总体而言，由于 PD 导致的背侧注意网络功能障碍似乎是 MCI 的标志，从而扩展了先前在非运动网络中发现的脑连接破坏的发现。
