Relationships between Beta-Amyloid and Functional Connectivity in Different Components of the Default Mode Network in Aging
Relationships between Beta-Amyloid and Functional Connectivity in Different Components of the Default Mode Network in Aging
复制标题
DOI：
10.1093/cercor/bhr025
复制
发表时间：
2011-10-01
期刊：
影响因子：
3.7
通讯作者：
Jagust, William J.
中科院分区：
文献类型：
--
作者：
Mormino, Elizabeth C.;Smiljic, Andre;Jagust, William J.
虽然β-淀粉样蛋白(A-beta)沉积是阿尔茨海默病(AD)的一个特征，但这种病理通常在老年正常对照组(NC)中发现。匹兹堡复合B正电子发射断层扫描(PIB-PET)成像检测到的Aβ沉积模式与默认模式网络(DMN)有很大的空间重叠，DMN是一组在外部驱动的认知任务中通常处于停用状态的大脑区域。在这项研究中，我们表明，在休息期间，DMN功能连接性(FC)随着NC摄取PIB水平的增加而改变。具体地说，在与情景记忆(EM)加工有关的区域(后内侧皮质、腹侧前额叶皮质和角回)，FC降低，而在背侧和前内侧前额叶和外侧颞叶皮质检测到连接性增加。这一下降模式与之前的研究一致，这些研究表明AD患者EM相关脑区的脆弱性增加，而Fc的增加可能反映了一种代偿反应。
Although beta-amyloid (A beta) deposition is a characteristic feature of Alzheimer's disease (AD), this pathology is commonly found in elderly normal controls (NC). The pattern of A beta deposition as detected with Pittsburgh compound-B positron emission tomography (PIB-PET) imaging shows substantial spatial overlap with the default mode network (DMN), a group of brain regions that typically deactivates during externally driven cognitive tasks. In this study, we show that DMN functional connectivity (FC) during rest is altered with increasing levels of PIB uptake in NC. Specifically, FC decreases were identified in regions implicated in episodic memory (EM) processing (posteromedial cortex, ventral medial prefrontal cortex, and angular gyrus), whereas connectivity increases were detected in dorsal and anterior medial prefrontal and lateral temporal cortices. This pattern of decreases is consistent with previous studies that suggest heightened vulnerability of EM-related brain regions in AD, whereas the observed increases in FC may reflect a compensatory response.