Social, Life, and Engineering Sciences Imaging Center, The Pennsylvania State University, University Park, PA, USA.
Department of Psychology, The Pennsylvania State University, University Park, PA, USA.
Neurobiol Aging. 2021 May;101:262-272. doi: 10.1016/j.neurobiolaging.2020.10.025. Epub 2020 Dec 11.
Aging is often associated with cognitive and neural decline, but how these factors interact is still not fully understood. Recently, functional connectivity, or the degree to which brain regions are concurrently active, has provided insight into age-related differences. However, functional connectivities during task and rest differ and few studies have examined how these relate to a broad range of cognitive functions. The present study investigated the effect of age on cognition, whole-brain functional connectivity during resting-state and task, and their relationships across the adult lifespan. Cognition was broadly assessed using a battery of cognitive assessments and mean network characteristics were calculated across the whole brain. Behaviorally, increased age was associated with worse recall, executive function, and verbal working memory abilities but better language performance. Neurally, increased age was associated with lower overall within- and between-network functional connectivities during both rest and task, and these age-connectivity relationships were stronger during task performance. Connectivity was also related to cognition, and for all participants, these relationships were strongest during rest. Specifically, higher resting-state between-network functional connectivity was associated with poorer cognition for all adults and poorer language ability among older adults. Collectively, these findings demonstrate that while age effects were strongest during the task, resting-state functional connectivity was most closely tied to cognition. Moreover, these results are theoretically consistent with dedifferentiation accounts of cognition and aging and show that less differentiated functional connectivities are associated with cognitive costs for both older and younger adults.
衰老通常与认知和神经功能下降有关，但这些因素如何相互作用仍不完全清楚。最近，功能连接，即大脑区域同时活跃的程度，为研究与年龄相关的差异提供了新的视角。然而，任务和休息期间的功能连接不同，很少有研究探讨它们与广泛的认知功能的关系。本研究调查了年龄对认知、静息状态和任务期间全脑功能连接的影响，以及它们在整个成年期的关系。使用一系列认知评估广泛评估认知，计算整个大脑的平均网络特征。行为上，随着年龄的增长，回忆、执行功能和言语工作记忆能力下降，但语言表现更好。神经上，静息和任务期间的整体内部和网络间功能连接性随年龄增长而降低，并且在任务表现期间，这些年龄连接性关系更强。连接性也与认知有关，对于所有参与者，这些关系在静息时最强。具体来说，对于所有成年人，静息状态下的网络间功能连接性越高，认知能力越差，而对于老年人，语言能力越差。总的来说，这些发现表明，虽然年龄效应在任务期间最强，但静息状态功能连接性与认知最密切相关。此外，这些结果在理论上与认知和衰老的去分化理论一致，表明功能连接性的差异较小与老年人和年轻人的认知成本相关。
