目的:本研究的目的是比较帕金森病伴轻度认知障碍(PD-MCI)患者和帕金森病伴认知正常(PD-CN)患者默认模式网络(DMN)子系统中有效连接的差异。目的是研究PD-MCI患者DMN功能障碍的潜在机制及其与PD-MCI临床认知功能的关系。
方法:频谱动态因果模型(spDCM)用于分析DMN子系统在静息状态下功能磁共振成像(fMRI)数据的有效连通性,其中包括内侧前额叶皮层(MPFC),后扣带皮质(PCC),左右角回(LAG,RAG)在23例PD-MCI和22例PD-CN患者中,分别。采用双样本t检验对两组DMN子系统的有效连通性值进行统计学分析。采用Spearman相关分析检验两组间存在显著差异的子系统有效连接值与临床认知功能(以蒙特利尔认知评估量表(MoCA)评分测量)的相关性。
结果:统计学分析显示MPFC-LAG和LAG-PCC有效连接在两个患者组之间存在显著差异(MPFC-LAG:t=-2.993,p<0.05;LAG-PCC:t=2.174,p<0.05)。
结论:研究结果表明,在PD-MCI患者中发现了DMN子系统之间有效连接的异常强度和方向。
OBJECTIVE: The objective of this study is to compare the differences in effective connectivity within the default mode network (DMN) subsystems between patients with Parkinson\'s disease with mild cognitive impairment (PD-MCI) and patients with Parkinson\'s disease with normal cognition (PD-CN). The mechanisms underlying DMN dysfunction in PD-MCI patients and its association with clinical cognitive function in PD-MCI are aimed to be investigated.
METHODS: The spectral dynamic causal model (spDCM) was employed to analyze the effective connectivity of functional magnetic resonance imaging (fMRI) data in the resting state for the DMN subsystems, which include the medial prefrontal cortex (MPFC), posterior cingulate cortex (PCC), left and right angular gyrus (LAG, RAG) in 23 PD-MCI and 22 PD-CN patients, respectively. The effective connectivity values of DMN subsystems in the two groups were statistically analyzed using a two-sample t-test. The Spearman correlation analysis was used to test the correlation between the effective connectivity values of the subsystems with significant differences between the two groups and the clinical cognitive function (as measured by Montreal Cognitive Assessment Scale (MoCA) score).
RESULTS: Statistical analysis revealed significant differences in the effective connections of MPFC-LAG and LAG-PCC between the two patient groups (MPFC-LAG: t = -2.993, p < 0.05; LAG-PCC: t = 2.174, p < 0.05).
CONCLUSIONS: The study findings suggest that abnormal strength and direction of effective connections between DMN subsystems are found in PD-MCI patients.