METHODS: A total of 229 cognitively intact participants were included from the Alzheimer\'s Disease Neuroimaging Initiative dataset and further divided into four groups based on the \"A/T\" profile using amyloid and tau positron emission tomography (PET). All A-T+ subjects were excluded. One hundred and seventy-three subjects along the Alzheimer\'s continuum (A-T-, A+ T-, A+ T+) were used for further study. The seed-based functional connectivity (FC) maps of the BF subregions (Ch1-3 and Ch4 [nucleus basalis of Meynert, NBM]) with whole-brain voxels were constructed. Analyses of covariance to detect the between-group differences and to further investigated the relations between FC values and AD biomarkers or cognition.
RESULTS: We found increased FC between right Ch4 and bilateral amygdala among three groups, and the FC value could well distinguish between the A-T- group and the Alzheimer\'s continuum groups. Furthermore, increased FC between the Ch4 and amygdala was associated with higher pathological burden reflected by amyloid and tau PET in the entire population as well as better logistic memory function in A + T+ group.
CONCLUSIONS: Our study demonstrated the NBM functional connectivity increased in cognitively normal elderly along the Alzheimer\'s continuum, which indicated a potential compensatory mechanism to counteract pathological changes in AD and maintain intact cognitive function.
方法:共有229名认知完整的参与者从阿尔茨海默病神经影像学计划数据集中纳入,并根据使用淀粉样蛋白和tau正电子发射断层扫描(PET)的“A/T”图进一步分为四组。排除所有A-T+受试者。沿着阿尔茨海默氏症的连续体,一百七十三个受试者(A-T-,A+T-,A+T+)用于进一步研究。BF亚区(Ch1-3和Ch4[Meynert的基底核,构建了具有全脑体素的NBM])。分析协方差以检测组间差异,并进一步研究FC值与AD生物标志物或认知之间的关系。
结果:我们发现三组中右侧Ch4和双侧杏仁核之间的FC增加,FC值可以很好地区分A-T组和阿尔茨海默氏症连续体组。此外,Ch4和杏仁核之间的FC增加与整个人群中淀粉样蛋白和tauPET反映的更高的病理负担以及AT组更好的逻辑记忆功能相关。
结论:我们的研究表明,认知正常的老年人的NBM功能连接在阿尔茨海默氏症的连续体中增加,这表明潜在的代偿机制可以抵消AD的病理变化并维持完整的认知功能。