Exploring Cognitive Aging Using Reference Ability Neural Networks

描述（由申请人提供）：已经反复证明，在各种认知测试的大电池上的跨年龄跨度的表现可以由一组四种参考能力来简约地表示：情景记忆，感知速度，流体能力和词汇。基于这些发现，Salthouse等人认为，认知老化研究的一个富有成效和有效的方法是试图了解老化如何影响这一小部分参考能力的表现，而不是具体任务。相比之下，神经影像学研究人员通常会评估与单一特定任务相关的神经激活的年龄差异，这些任务可能会或可能不会完全代表这些参考能力。我们建议识别与Salthouse的4个参考能力中的每一个相关的潜伏脑网络。在进行功能成像时，我们将测试375名健康成年人（20至50岁每10年50人，50至80岁每10年75人），其中一系列12项认知任务代表四种参考能力（每个结构3项）。使用空间协方差和其他分析的功能磁共振成像数据的独特的专业知识，我们将得出潜在的空间，全脑功能磁共振成像网络与整个成年期的参考能力的潜在认知结构。这些“参考能力神经网络”的成功识别可能会导致一个范式的转变，在认知的年龄差异的神经基础的研究，通过关注广泛的和可复制的方面共同的几个任务，而不是个别任务的可能特质的功能。在确定这些参考能力神经网络后，我们将使用多模态成像来评估网络利用率中与年龄相关差异的潜在介质。这些潜在介质包括脑容量和皮质厚度的变化;白色高信号负荷;白色束的完整性;静息CBF;和默认网络。拟议中的fMRI研究将为认知老化的研究开发一种全新的、更集中的成像方法。结合与年龄相关的大脑变化和病理学的多模态成像，该项目有可能为认知老化的神经变化的性质和原因提供关键见解。

DESCRIPTION (provided by applicant): 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, Salthouse et al. have argued that a productive and efficient approach to cognitive aging research is to try to understand how aging impacts performance of this small set of reference abilities than 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 propose to identify the latent brain networks associated with each of Salthouse's 4 reference abilities across adulthood. While undergoing functional imaging, we will test 375 healthy adults (50 per decade from age 20 to 50, 75 per decade for 50 to 80) with a series of 12 cognitive tasks that represent four reference abilities (3 per construct). Using unique expertise in spatial covariance and other analyses of the fMRI imaging data, we will derive 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. After identifying these reference ability neural networks, we will use multimodal imaging to evaluate potential mediators of age-related differences in the utilization of the networks. These potential mediators will include change in brain volume and cortical thickness; white matter hyperintensity burden; integrity of white matter tracts; resting CBF; and the default network. The proposed fMRI study will develop a completely new and more focused imaging approach to the study of cognitive aging. In combination with the multimodal imaging of age-related brain changes and pathology, this project has the potential to provide key insights into the nature and causes of the neural changes that underlie cognitive aging.