Effects of beta-amyloid accumulation on neural function during encoding across the adult lifespan.
Effects of beta-amyloid accumulation on neural function during encoding across the adult lifespan.
复制标题
DOI：
10.1016/j.neuroimage.2012.03.077
复制
发表时间：
2012-08-01
期刊：
影响因子：
5.7
通讯作者：
Park, Denise C.
中科院分区：
文献类型：
--
作者：
Kennedy, Kristen M.;Rodrigue, Karen M.;Devous, Michael D., Sr.;Hebrank, Andrew C.;Bischof, Gerard N.;Park, Denise C.
有限的功能成像证据表明，即使在健康的老年人中，β-淀粉样蛋白沉积的增加也与大脑功能的改变有关。然而，这些发现中的大多数都是关于60岁以上成年人的静息状态活动或功能连接的。关于β-淀粉样蛋白对认知任务执行过程中神经激活的影响，或者淀粉样蛋白对年轻人和中年人的影响，我们知道的要少得多。目前的这项研究使用18Florbetapir从PET成像中测量了大量连续年龄的高筛查健康成年人(N=137；年龄30-89岁)的β-淀粉样蛋白负荷。同样的参与者还接受了fMRI扫描，执行记忆编码任务。使用β-淀粉样蛋白负荷和年龄作为编码活性的连续预测因子，我们报告了超越年龄影响的β-淀粉样蛋白负荷对神经功能的剂量-反应关系。具体地说，淀粉样蛋白负荷较大的个体在双侧背外侧前额叶皮质表现出较少的神经激活，这是一个对记忆编码至关重要的区域，以及与默认网络活动相关的区域：双侧上/内侧额叶和外侧颞叶皮质的神经调制减少。重要的是，这种作为淀粉样蛋白负荷的函数的激活和抑制的减少在整个生命周期中都被发现，即使在年轻人和中年人中也是如此。此外，额叶和颞叶淀粉样蛋白减少的激活/抑制与较慢的处理速度、语言流利性和流畅推理有关，这表明它在本质上是有害的，而不是补偿的。
Limited functional imaging evidence suggests increased beta-amyloid deposition is associated with alterations in brain function, even in healthy older adults. However, the majority of these findings report on resting-state activity or functional connectivity in adults over age 60. Much less is known about the impact of beta-amyloid on neural activations during cognitive task performance, or the impact of amyloid in young and middle-aged adults. The current study measured beta-amyloid burden from PET imaging using18Florbetapir, in a large continuous age sample of highly-screened, healthy adults (N = 137; aged 30–89 years). The same participants also underwent fMRI scanning, performing a memory encoding task. Using both beta-amyloid burden and age as continuous predictors of encoding activity, we report a dose-response relationship of beta-amyloid load to neural function, beyond the effects of age. Specifically, individuals with greater amyloid burden evidence less neural activation in bilateral dorsolateral prefrontal cortex, a region important for memory encoding, as well as reduced neural modulation in areas associated with default network activity: bilateral superior/medial frontal and lateral temporal cortex. Importantly, this reduction of both activation and suppression as a function of amyloid load was found across the lifespan, even in young- and middle-aged individuals. Moreover, this frontal and temporal amyloid-reduced activation/suppression was associated with poorer processing speed, verbal fluency, and fluid reasoning in a subgroup of individuals with elevated amyloid, suggesting that it is detrimental, rather than compensatory in nature.
登录
查看更多内容
DOI：
10.1093/geronb/gbq035
发表时间：
2010-07-01
影响因子：
6.2
作者：
Reuter-Lorenz, Patricia A.;Park, Denise C.
通讯作者：
Park, Denise C.
影响因子：
24.8
作者：
Park DC;Reuter-Lorenz P
通讯作者：
Reuter-Lorenz P
影响因子：
14.5
作者：
Pike, Kerryn E.;Savage, Greg;Rowe, Christopher C.
通讯作者：
Rowe, Christopher C.
影响因子：
16.2
作者：
Sperling, Reisa A.;LaViolette, Peter S.;O'Keefe, Kelly;O'Brien, Jacqueline;Rentz, Dorene M.;Pihlajamaki, Maija;Marshall, Gad;Hyman, Bradley T.;Selkoe, Dennis J.;Hedden, Trey;Buckner, Randy L.;Becker, J. Alex;Johnson, Keith A.
通讯作者：
Johnson, Keith A.
影响因子：
10.6
作者：
Sheline YI;Raichle ME;Snyder AZ;Morris JC;Head D;Wang S;Mintun MA
通讯作者：
Mintun MA