Exploring Cognitive Aging Using Refernce Ability Neural Networks

项目总结： 本研究的重点是认知老化的最佳功能和结构成像特征。 临床前阿尔茨海默病(AD)。多年来的表现已被反复证明 不同认知测试的大电池的跨度可以用一组四个参考来简略地表示 能力：情景记忆、感知速度、流畅能力和词汇量。基于这些发现， 认为认知老化研究应该试图理解衰老如何影响这一小部分人的表现 而不是专注于特定的任务。相比之下，神经成像研究人员通常会评估年龄 神经激活的差异与单个特定任务的表现有关，这可能或可能不 完全代表这些参考能力。我们已经开始识别潜伏的大脑网络 与成年后的四种参考能力中的每一种有关。在接受功能成像的同时，我们 对一大群年龄在20岁到80岁之间的健康成年人进行了一系列12项认知任务的测试，这些任务代表四项任务 参考异能(每个构造物3个)。利用空间协方差和其他分析方面的独特专业知识 FMRI成像数据，我们已经得出了潜在的空间、全脑fMRI网络的初步版本 与成年期参照能力的潜在认知结构有关。成功 这些“参考能力神经网络”的识别可能会导致神经研究的范式转变。 通过关注几个任务共有的广泛和可复制的方面来考察年龄认知差异的基础 而不是个别任务可能的特殊特征。我们现在建议在5点对这个小组进行跟进 为了开始描绘这些网络的表达如何随着年龄的增长和随着疾病的开始而变化 轻度认知障碍和阿尔茨海默病。我们将使用多模式成像来评估潜在的年龄和 与痴呆症相关的网络利用差异。这些变化包括大脑体积的变化和 皮质厚度；白质高强度负荷；白质束完整性；静息CBF； 默认网络。重要的是，我们将使用正电子发射计算机断层扫描来评估淀粉样蛋白负荷。拟议的研究将制定一项 研究认知老化和临床前阿尔茨海默病的全新和更有针对性的成像方法。它有 对构成认知基础的神经变化的本质和原因提供关键见解的潜力 更准确地描述阿尔茨海默病的临床前阶段。

PROJECT SUMMARY: This study focus on the optimal functional and structural imaging characterization of the cognitive aging and preclinical Alzheimer's disease (AD). It has been repeatedly demonstrated that performance across the age span on large batteries of diverse cognitive tests can be parsimoniously represented by a set of four reference abilities: episodic memory, perceptual speed, fluid ability, and vocabulary. Based on these findings, it has been argued that cognitive aging research should try to understand how aging impacts performance of this small set of reference abilities than focus on specific tasks. In contrast, neuroimaging researchers typically evaluate age differences in neural activation associated with the performance of a single specific task that may or may not be fully representative of these reference abilities. We have begun to identify the latent brain networks associated with each of the four reference abilities across adulthood. While undergoing functional imaging, we tested large group of healthy adults aged 20 to 80 with a series of 12 cognitive tasks that represent the four reference abilities (3 per construct). Using unique expertise in spatial covariance and other analyses of the fMRI imaging data, we have derived preliminary versions of the latent spatial, brain-wide fMRI networks that are associated with the latent cognitive structure of the reference abilities across adulthood. Successful identification of these "reference ability neural networks" may lead to a paradigm shift in research on the neural bases of age differences in cognition by focusing on the broad and replicable aspects common to several tasks rather than the possibly idiosyncratic features of individual tasks. We now propose to follow up this group at 5 years in order to begin to delineate how expression of these networks changes with aging and with the onset of mild cognitive impairment and AD. We will use multimodal imaging to evaluate potential mediators of age and dementia-related differences in the utilization of the networks. These include change in brain volume and cortical thickness; white matter hyperintensity burden; integrity of white matter tracts; resting CBF; and the default network. Importantly, we will use PET to assess amyloid burden. The proposed study will develop a completely new and more focused imaging approach to the study of cognitive aging and preclinical AD. It has the potential to provide key insights into the nature and causes of the neural changes that underlie cognitive aging and to more accurately describe the preclinical phase of AD.