Bernard Jessica A, Peltier Scott J, Wiggins Jillian Lee, Jaeggi Susanne M, Buschkuehl Martin, Fling Brett W, Kwak Youngbin, Jonides John, Monk Christopher S, Seidler Rachael D
Department of Psychology, University of Michigan, USA.
Neuroimage. 2013 Dec;83:103-19. doi: 10.1016/j.neuroimage.2013.06.042. Epub 2013 Jun 20.
Healthy aging is marked by declines in a variety of cognitive and motor abilities. A better understanding of the aging brain may aid in elucidating the neural substrates of these behavioral effects. Investigations of resting state functional brain connectivity have provided insights into pathology, and to some degree, healthy aging. Given the role of the cerebellum in both motor and cognitive behaviors, as well as its known volumetric declines with age, investigating cerebellar networks may shed light on the neural bases of age-related functional declines. We mapped the resting state networks of the lobules of the right hemisphere and the vermis of the cerebellum in a group of healthy older adults and compared them to those of young adults. We report disrupted cortico-cerebellar resting state network connectivity in older adults. These results remain even when controlling for cerebellar volume, signal-to-noise ratio, and signal-to-fluctuation noise ratio. Specifically, there was consistent disruption of cerebellar connectivity with both the striatum and the medial temporal lobe. Associations between connectivity strength and both sensorimotor and cognitive task performances indicate that cerebellar engagement with the default mode network and striatal pathways is associated with better performance for older adults. These results extend our understanding of the resting state networks of the aging brain to include cortico-cerebellar networks, and indicate that age differences in network connectivity strength are important for behavior.
健康衰老的特征是多种认知和运动能力下降。更好地了解衰老大脑可能有助于阐明这些行为效应的神经基础。对静息态功能脑连接的研究为病理学以及在一定程度上为健康衰老提供了见解。鉴于小脑在运动和认知行为中的作用，以及其已知的随年龄增长的体积减小，研究小脑网络可能有助于揭示与年龄相关的功能衰退的神经基础。我们绘制了一组健康老年人右半球小叶和小脑蚓部的静息态网络，并将其与年轻人的进行比较。我们报告了老年人皮质-小脑静息态网络连接中断。即使在控制了小脑体积、信噪比和信号与波动噪声比之后，这些结果仍然存在。具体而言，小脑与纹状体和内侧颞叶之间的连接存在持续中断。连接强度与感觉运动和认知任务表现之间的关联表明，小脑与默认模式网络和纹状体通路的参与与老年人更好的表现相关。这些结果扩展了我们对衰老大脑静息态网络的理解，将皮质-小脑网络包括在内，并表明网络连接强度的年龄差异对行为很重要。
