Age-related differences in cortical recruitment and suppression: Implications for cognitive performance
Age-related differences in cortical recruitment and suppression: Implications for cognitive performance
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DOI：
10.1016/j.bbr.2012.01.058
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发表时间：
2012-04-21
影响因子：
2.7
通讯作者：
Kramer, Arthur F.
中科院分区：
文献类型：
--
作者：
Prakash, Ruchika Shaurya;Heo, Susie;Kramer, Arthur F.
一组连贯的皮质区域在休息时显示激活，在任务执行时显示失活，这一发现重新引发了神经科学领域的一场古老辩论，这场辩论质疑人类大脑的反射性，并为更内在的功能结构提供了证据。默认模式网络（DMN）包括这样一致的皮层区域已成为一个话题，越来越多的兴趣在健康和患病人群。在这项研究中，使用一个良好的检查版本的口头n-回任务，交错与休息块的时间，我们调查是否失活的皮质区，包括DMN温和的行为表现在一组老年人的个体差异。我们招募了25名年轻人和25名老年人进行研究，并向他们展示了n-back任务的模块，不同程度的负荷，与固定时间交错。对年轻和老年参与者的直接比较显示，随着任务需求的增加，前额叶和顶叶区域的上调减少，沿着老年人随着认知负荷的增加，DMN区域的下调减少。年轻人的更好的表现与随着任务难度的增加而调节工作记忆网络区域的能力有关，然而，老年人的增强表现与更大的负荷诱导的后扣带皮层失活有关。这项研究增加了现有的老龄化文献的范围，提供证据表明DMN功能对老年人的认知功能至关重要。由爱思唯尔公司出版
The discovery of a coherent set of cortical regions showing activation during rest and deactivation during task performance has reignited an old debate in the field of neuroscience, one that questions the reflexivity of the human brain and provides evidence towards a more intrinsic functional architecture. The default-mode network (DMN) comprising of such consistent cortical regions has become a topic of increasing interest in both healthy and diseased populations. In this study, using a well-examined version of the verbal n-back task, interleaved with periods of rest blocks, we investigated whether the deactivation of the Cortical regions comprising the DMN moderates individual differences in behavioral performance in a group of older adults. We recruited 25 young and 25 older adults for our study and presented them with blocks of the n-back task, with varying levels of load, interleaved with periods of fixation. A direct comparison of the young and older participants revealed both a reduction in the up-regulation of the prefrontal and parietal regions in response to increasing task demands, along with a reduction in the down-regulation of DMN regions with increasing cognitive load in the elderly. Better performance in the young adults was associated with the capability to modulate the regions of the working memory network with increasing task difficulty, however enhanced performance in the older cohort was associated with greater load-induced deactivation of the posterior cingulate cortex. This study adds to the existing gamut of aging literature, providing evidence that DMN function is critical to cognitive functioning in older adults. Published by Elsevier B.V.