Hoffstaedter F, Grefkes C, Roski C, Caspers S, Zilles K, Eickhoff S B
Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, 52425, Jülich, Germany,
Brain Struct Funct. 2015 Mar;220(2):999-1012. doi: 10.1007/s00429-013-0696-2. Epub 2014 Jan 8.
Healthy aging is accompanied by a decrease in cognitive and motor capacities. In a network associated with movement initiation, we investigated age-related changes of functional connectivity (FC) as well as regional atrophy in a sample of 232 healthy subjects (age range 18-85 years). To this end, voxel-based morphometry and whole-brain resting-state FC were analyzed for the supplementary motor area (SMA), anterior midcingulate cortex (aMCC) and bilateral striatum (Str). To assess the specificity of age-related effects, bilateral primary sensorimotor cortex (S1/M1) closely associated with motor execution was used as control seeds. All regions showed strong reduction of gray matter volume with age. Corrected for this regional atrophy, the FC analysis revealed an age × seed interaction for each of the bilateral Str nodes against S1/M1 with consistent age-related decrease in FC with bilateral caudate nucleus and anterior putamen. Specific age-dependent FC decline of SMA was found in bilateral central insula and the adjacent frontal operculum. aMCC showed exclusive age-related decoupling from the anterior cingulate motor area. The present study demonstrates network as well as node-specific age-dependent FC decline of the SMA and aMCC to highly integrative cortical areas involved in cognitive motor control. FC decrease in addition to gray matter atrophy within the Str may provide a substrate for the declining motor control in elderly. Finally, age-related FC changes in both the network for movement initiation as well as the network for motor execution are not explained by regional atrophy in the healthy aging brain.
健康衰老伴随着认知和运动能力的下降。在一个与运动发起相关的网络中，我们在232名健康受试者（年龄范围18 - 85岁）的样本中研究了功能连接性（FC）的年龄相关变化以及区域萎缩情况。为此，对辅助运动区（SMA）、前扣带回中部皮质（aMCC）和双侧纹状体（Str）进行了基于体素的形态学分析和全脑静息态FC分析。为了评估年龄相关效应的特异性，将与运动执行密切相关的双侧初级感觉运动皮质（S1/M1）用作对照种子。所有区域的灰质体积均随年龄显著减少。校正这种区域萎缩后，FC分析显示，双侧Str节点中每个节点与S1/M1之间存在年龄×种子交互作用，与双侧尾状核和壳核前部的FC呈现一致的年龄相关下降。在双侧中央脑岛和相邻的额下回发现了SMA特定的年龄依赖性FC下降。aMCC显示出与前扣带回运动区仅有的年龄相关去耦联。本研究表明，SMA和aMCC的网络以及节点特异性年龄依赖性FC下降至参与认知运动控制的高度整合皮质区域。Str内除灰质萎缩外的FC下降可能为老年人运动控制能力下降提供了一个基础。最后，健康衰老大脑中运动发起网络和运动执行网络中与年龄相关的FC变化不能用区域萎缩来解释。
