Hong Xiangfei, Liu Yuelu, Sun Junfeng, Tong Shanbao
Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of MedicineShanghai, China; School of Biomedical Engineering, Shanghai Jiao Tong UniversityShanghai, China.
Center for Mind and Brain, University of California Davis, CA, USA.
Front Aging Neurosci. 2016 May 17;8:100. doi: 10.3389/fnagi.2016.00100. eCollection 2016.
Although inter-regional phase synchrony of neural oscillations has been proposed as a plausible mechanism for response control, little is known about the possible effects due to normal aging. We recorded multi-channel electroencephalography (EEG) from healthy younger and older adults in a Go/NoGo task, and examined the aging effects on synchronous brain networks with graph theoretical analysis. We found that in both age groups, brain networks in theta, alpha or beta band for either response execution (Go) or response inhibition (NoGo) condition showed prominent small-world property. Furthermore, small-world property of brain networks showed significant differences between different task conditions. Further analyses of node degree suggested that frontal-central theta band phase synchrony was enhanced during response inhibition, whereas during response execution, increased phase synchrony was observed in beta band over central-parietal regions. More interestingly, these task-related modulations on brain networks were well preserved and even more robust in older adults compared with younger adults. Taken together, our findings not only suggest that response control involves synchronous brain networks in functionally-distinct frequency bands, but also indicate an increase in the recruitment of brain network resources due to normal aging.
尽管神经振荡的区域间相位同步已被提出是一种合理的反应控制机制，但对于正常衰老可能产生的影响却知之甚少。我们在一项“Go/NoGo任务”中记录了健康年轻人和老年人的多通道脑电图（EEG），并通过图论分析研究了衰老对同步脑网络的影响。我们发现，在两个年龄组中，无论是反应执行（Go）还是反应抑制（NoGo）条件下，θ、α或β频段的脑网络均表现出显著的小世界特性。此外，脑网络的小世界特性在不同任务条件之间存在显著差异。对节点度的进一步分析表明，在反应抑制期间，额中央θ频段的相位同步增强，而在反应执行期间，中央顶叶区域的β频段观察到相位同步增加。更有趣的是，与年轻人相比，老年人中这些与任务相关的脑网络调制得到了很好的保留，甚至更加稳健。综上所述，我们的研究结果不仅表明反应控制涉及功能上不同频段的同步脑网络，还表明正常衰老会导致脑网络资源募集增加。
