KU Leuven, Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Biomedical Sciences, Leuven, Belgium.
Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, The Netherlands.
Cereb Cortex. 2018 Dec 1;28(12):4390-4402. doi: 10.1093/cercor/bhx297.
Aging is typically associated with substantial declines in motor functioning as well as robust changes in the functional organization of brain networks. Previous research has investigated the link between these 2 age-varying factors but examinations were predominantly limited to the functional organization within motor-related brain networks. Little is known about the relationship between age-related behavioral impairments and changes in functional organization at the whole brain (i.e., multiple network) level. This knowledge gap is surprising given that the decreased segregation of brain networks (i.e., increased internetwork connectivity) can be considered a hallmark of the aging process. Accordingly, we investigated the association between declines in motor performance across the adult lifespan (20-75 years) and age-related modulations of functional connectivity within and between resting state networks. Results indicated that stronger internetwork resting state connectivity observed as a function of age was significantly related to worse motor performance. Moreover, performance had a significantly stronger association with the strength of internetwork as compared with intranetwork connectivity, including connectivity within motor networks. These findings suggest that age-related declines in motor performance may be attributed to a breakdown in the functional organization of large-scale brain networks rather than simply age-related connectivity changes within motor-related networks.
衰老通常与运动功能的显著下降以及大脑网络功能组织的显著变化有关。先前的研究已经调查了这两个随年龄变化的因素之间的联系，但检查主要限于与运动相关的大脑网络内的功能组织。关于与年龄相关的行为障碍和整个大脑（即多个网络）水平的功能组织变化之间的关系知之甚少。考虑到大脑网络的分离减少（即网络间连通性增加）可以被认为是衰老过程的一个标志，这种知识差距令人惊讶。因此，我们调查了整个成年期（20-75 岁）的运动表现下降与静息状态网络内和网络间功能连通性的年龄相关调节之间的关联。结果表明，随着年龄的增长而观察到的更强的网络间静息状态连通性与较差的运动表现显著相关。此外，与网络内连通性相比，运动网络内的连通性，运动表现与网络间连通性的强度具有更强的相关性。这些发现表明，与年龄相关的运动表现下降可能归因于大规模大脑网络的功能组织崩溃，而不仅仅是与运动相关网络内的与年龄相关的连通性变化。
