Interhemispheric functional connectivity for Alzheimer's disease and amnestic mild cognitive impairment based on the triple network model

基于三网络模式的阿尔茨海默病和遗忘型轻度认知功能障碍的半球间功能连接研究（英文）

The purpose of this study was to explore the differences in interhemispheric functional connectivity in patients with Alzheimer’s disease(AD) and amnestic mild cognitive impairment(aMCI) based on a triple network model consisting of the default mode network(DMN), salience network(SN), and executive control network(ECN). The technique of voxel-mirrored homotopic connectivity(VMHC) analysis was applied to explore the aberrant connectivity of all patients. The results showed that:(1) the statistically significant connections of interhemispheric brain regions included DMN-related brain regions(i.e. precuneus, calcarine, fusiform, cuneus, lingual gyrus, temporal inferior gyrus, and hippocampus), SN-related brain regions(i.e. frontoinsular cortex), and ECN-related brain regions(i.e. frontal middle gyrus and frontal inferior);(2) the precuneus and frontal middle gyrus in the AD group exhibited lower VMHC values than those in the aMCI and healthy control(HC) groups, but no significant difference was observed between the a MCI and HC groups; and(3) significant correlations were found between peak VMHC results from the precuneus and Mini Mental State Examination(MMSE) and Montreal Cognitive Scale(MOCA) scores and their factor scores in the AD, a MCI, and AD plus aMCI groups, and between the results from the frontal middle gyrus and MOCA factor scores in the a MCI group. These findings indicated that impaired interhemispheric functional connectivity was observed in AD and could be a sensitive neuroimaging biomarker for AD. More specifically, the DMN was inhibited, while the SN and ECN were excited. VMHC results were correlated with MMSE and MOCA scores, highlighting that VMHC could be a sensitive neuroimaging biomarker for AD and the progression from aMCI to AD.

目的:探讨阿尔茨海默病(AD)和遗忘型轻度认知功能障碍(aMCI)在默认脑网络(DMN)、突显网络(SN)和执行控制网络(ECN)这三个脑网络中的半球间脑功能连接的差异性。创新点:利用体素镜像同伦功能连接(VMHC)来观察AD和aMCI在多个脑网络基础上的半球间功能连接特点。方法:该研究纳入了浙江省人民医院就诊的30例AD患者、14例aMCI患者和18例老年健康对照者,均给予静息态功能磁共振扫描,利用VMHC进行数据分析,联合简易智力状态检查量表(MMSE)和蒙特利尔认知评估量表(MOCA)进行相关分析。结论:(1)位于三个脑网络的异常半球功能连接主要存在于AD组,可以作为AD诊断的一个敏感性指标;(2)VMHC值可以作为预测AD进展包括aMCI发展为AD的一个敏感性指标。