Age-related adaptations of brain function during a memory task are also present at rest.
Age-related adaptations of brain function during a memory task are also present at rest.
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DOI：
10.1016/j.neuroimage.2011.11.063
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发表时间：
2012-02-15
期刊：
影响因子：
5.7
通讯作者：
Mackay, C. E.
中科院分区：
文献类型：
--
作者：
Filippini, N.;Nickerson, L. D.;Beckmann, C. F.;Ebmeier, K. P.;Frisoni, G. B.;Matthews, P. M.;Smith, S. M.;Mackay, C. E.
一些研究已经证明了年龄相关的区域差异的幅度BOLD信号使用任务为基础的功能磁共振成像。有人认为，功能变化反映了补偿或去分化机制，这两种机制都假定对特定刺激的反应。在这里，我们测试了衰老是否会影响基于任务的和静息的大脑功能，以及功能变化在多大程度上是由灰质（GM）体积的减少介导的。两组，22名健康的年轻志愿者和22名老年志愿者，在记忆任务和休息期间进行了涉及结构和功能MRI的成像协议。两组具有相似的社会人口统计学特征和认知表现。图像分析显示结构和功能的差异。在老年志愿者中，BOLD信号相对于年轻志愿者的增加主要在额叶中观察到，无论是在任务期间还是在休息时。额叶的功能变化主要位于没有GM损失的大脑区域，在fMRI分析中加入GM协变量并没有显著改变组间差异。我们的研究结果与以下建议一致：在正常衰老期间，大脑通过微调备用神经元之间的连接来响应神经元损失。纵向研究将是必要的，以充分测试这一假设。
Several studies have demonstrated age-related regional differences in the magnitude of the BOLD signal using task-based fMRI. It has been suggested that functional changes reflect either compensatory or de-differentiation mechanisms, both of which assume response to a specific stimulus. Here, we have tested whether ageing affects both task-based and resting brain function, and the extent to which functional changes are mediated by reductions in grey matter (GM) volume. Two groups, of 22 healthy younger and 22 older volunteers, underwent an imaging protocol involving structural and functional MRI, both during a memory task and at rest. The two groups had similar socio-demographical characteristics and cognitive performance. Image analysis revealed both structural and functional differences. Increased BOLD signal in older relative to younger volunteers was mainly observed in the frontal lobes, both during the task and at rest. Functional changes in the frontal lobes were largely located in brain regions spared from GM loss, and adding GM covariates to the fMRI analysis did not significantly alter the group differences. Our results are consistent with the suggestion that, during normal ageing, the brain responds to neuronal loss by fine-tuning connections between spared neurons. Longitudinal studies will be necessary to fully test this hypothesis.
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影响因子：
3.7
作者：
Barnes A;Bullmore ET;Suckling J
通讯作者：
Suckling J
DOI：
10.1098/rstb.2005.1634
发表时间：
2005-05-29
影响因子：
6.3
作者：
Beckmann, CF;DeLuca, M;Smith, SM
通讯作者：
Smith, SM
DOI：
10.1161/01.atv.3.4.310
发表时间：
1983-01-01
期刊：
ARTERIOSCLEROSIS
影响因子：
--
作者：
MENZEL, HJ;KLADETZKY, RG;ASSMANN, G
通讯作者：
ASSMANN, G
影响因子：
5.7
作者：
Hayasaka, S;Phan, KL;Nichols, TE
通讯作者：
Nichols, TE
影响因子：
--
作者：
Fleisher, AS;Houston, WS;Bondi, MW
通讯作者：
Bondi, MW