State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, P. R. China.
BABRI Centre, Beijing Normal University, Beijing, P. R. China.
Cereb Cortex. 2020 Jan 10;30(1):326-338. doi: 10.1093/cercor/bhz090.
Age is the major risk factor for Alzheimer's disease (AD) and for mild cognitive impairment (MCI). However, there is limited evidence about MCI-specific aging-related simultaneous changes of the brain structure and their impact on cognition. We analyzed the brain imaging data from 269 subjects (97 MCI patients and 172 cognitively normal [CN] elderly) using voxel-based morphometry and tract-based spatial statistics procedures to explore the special structural pattern during aging. We found that the patients with MCI showed accelerated age-related reductions in gray matter volume in the left planum temporale, thalamus, and posterior cingulate gyrus. The similar age×group interaction effect was found in the fractional anisotropy of the bilateral parahippocampal cingulum white matter tract, which connects the temporal regions. Importantly, the age-related temporal gray matter and white matter alterations were more significantly related to performance in memory and attention tasks in MCI patients. The accelerated degeneration patterns in the brain structure provide evidence for different neural mechanisms underlying aging in MCI patients. Temporal structural degeneration may serve as a potential imaging marker for distinguishing the progression of the preclinical AD stage from normal aging.
年龄是阿尔茨海默病（AD）和轻度认知障碍（MCI）的主要危险因素。然而，关于 MCI 特异性与年龄相关的大脑结构同时变化及其对认知的影响的证据有限。我们使用基于体素的形态测量法和基于束流的空间统计学程序分析了 269 名受试者（97 名 MCI 患者和 172 名认知正常[CN]老年人）的脑成像数据，以探索衰老过程中的特殊结构模式。我们发现，MCI 患者的左颞平面、丘脑和后扣带回的灰质体积随年龄的增长而加速减少。在连接颞叶的双侧海马旁扣带白质束的各向异性分数中也发现了类似的年龄×组交互作用效应。重要的是，与记忆和注意力任务表现相关的与年龄相关的颞叶灰质和白质改变在 MCI 患者中更为显著。大脑结构的加速退化模式为 MCI 患者衰老的不同神经机制提供了证据。颞部结构的退化可能是将 AD 临床前阶段的进展与正常衰老区分开来的潜在影像学标志物。
