背景:在本研究中,我们调查了有认知选择的老年人与功能正常的老年人相比,淀粉样蛋白(Aβ)负担和人格特质的差异.责任心,特别是,与阿尔茨海默病(AD)病理有关,我们假设认知高的成年人会表现出更高的责任心。另外感兴趣的是达拉斯终身大脑研究中的高功能老年人是否会证明AD病理减少。
方法:我们测试了285名认知正常的参与者(年龄55-90岁),并使用修订的NEO人格量表(NEO-PI-R)收集了自觉性得分。参与者还接受了放射性示踪剂AV-45,18F-Florbetapir的PET成像,一种放射性示踪剂,用于测量大脑中的Aβ蛋白。计算了8个感兴趣的皮质区域的平均皮质SUVR,标准化为小脑灰质。此外,参与者完成了一个认知电池,做了核磁共振扫描,并完成抑郁和健康的自我报告。我们指定那些参与者得分等于或高于中年(35-54岁)参考组的平均情景记忆,作为“认知选择”(N=69),那些得分低于平均水平的人,如“认知正常”(N=216)。感兴趣的因变量包括全球和区域淀粉样蛋白(Aβ),皮质形态学,抑郁症,健身,尽责,和各种认知措施。
结果:认知选择的参与者更年轻(p=.043),受过更多的教育(p=.021),并且具有更高的积极人格特质,包括自律(p=0.01),对思想的开放(p=.013),和能力(p=.015),与认知正常相比。尽管各组在总体Aβ病理负荷方面没有差异(p=0.083),认知选择在包括颞侧区在内的特定区域表现出较少的病理(p=.049)。回归分析控制性别,年龄,教育,MMSE,通过全局Aβ相互作用对流体能力的影响揭示了一个显著的群体(p=.034),其中较大的Aβ负荷仅在认知正常的老年人中预测较低的得分。
结论:这些发现提供了证据,表明认知特权的成年人在许多领域表现出对衰退的抵抗力,并表现出对淀粉样蛋白病理学的抵抗力。讨论将集中在淀粉样蛋白积累的纵向变化,皮质变薄,和认知能力下降,以及储备的概念。
BACKGROUND: In the present study, we investigated differences in amyloid (Aβ) burden and personality traits in cognitively-select older adults compared to average-functioning older adults. Conscientiousness, in particular, has been linked to Alzheimer\'s Disease (AD) pathology, and we hypothesized that adults who were high in cognition would exhibit enhanced conscientiousness. Of additional interest was whether high functioning older adults in the Dallas Lifespan Brain Study would evidence reduced AD pathology.
METHODS: We tested 285 cognitively-normal participants (ages 55-90) and collected conscientiousness scores using the Revised NEO Personality Inventory (NEO-PI-R). Participants also underwent PET imaging with radiotracer AV-45, 18F-Florbetapir, a radiotracer that is used to measure Aβ protein in the brain. Mean cortical SUVR was computed across 8 cortical regions of interest, normalized to cerebellar gray matter. In addition, participants completed a cognitive battery, underwent an MRI scan, and completed self-reports for depression and fitness. We designated those participants scoring at or above the mean episodic memory of a middle-aged (ages 35-54) reference group, as \"cognitively-select\" (N = 69), and those scoring below the mean, as \"cognitively-normal\" (N = 216). Dependent variables of interest included global and regional amyloid (Aβ), cortical morphometry, depression, fitness, conscientiousness, and various cognitive measures.
RESULTS: Cognitively select participants were younger (p = .043), more educated (p = .021), and had higher positive personality traits, including self-discipline (p = .01), openness to ideas (p = .013), and competence (p = .015), compared to cognitively-normal. Although the groups did not differ in global Aβ pathology load (p = .083), cognitively select exhibited less pathology in specific regions including lateral temporal areas (p = .049). Regression analysis controlling for sex, age, education, and MMSE, revealed a significant group by global Aβ interaction on fluid ability (p = .034), where greater Aβ load predicted lower scores in cognitively normal older adults only.
CONCLUSIONS: These findings provide evidence that cognitively privileged adults show resistance to decline across many domains and demonstrate resilience to amyloid pathology. Discussion will focus on longitudinal change in amyloid accumulation, cortical thinning, and cognitive decline, as well as the concept of reserve.