Influence of coherence between multiple cortical columns on alpha rhythm: A computational modeling study
Influence of coherence between multiple cortical columns on alpha rhythm: A computational modeling study
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DOI：
10.1002/hbm.20899
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发表时间：
2009-11
影响因子：
4.8
通讯作者：
Y. Naruse;A. Matani;Y. Miyawaki;M. Okada
中科院分区：
文献类型：
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作者：
Y. Naruse;A. Matani;Y. Miyawaki;M. Okada
在脑电图（EEG）和脑磁图（MEG）信号中，刺激诱导的α节律振幅的增加和减少，称为事件相关的同步和去同步（ERS/ERD），在任务开始后出现。ERS/ERD被认为反映了与认知任务相关的神经过程。先前的研究表明，在大脑皮层中存在着几个α节律源，每一个都可以作为α节律发生器。由于脑电/脑磁图信号代表空间上的神经活动总和，因此，α节律的ERS/ERD可能反映了多个α节律发生器之间相互作用的结果。两个候选调节ERS/ERD的大小：(1)α节律发生器活动之间的一致性和(2)α节律发生器活动的平均振幅。在这项研究中，我们使用多个α节律发生器的计算模型来确定导致ERS/ERD的主要因素。每个阿尔法节律发生器都是基于初级视觉皮层的局部列电路建模的，并通过兴奋性连接与邻近的发生器相互作用。我们观察到，该模型在特定的连接系数范围内一致地再现了自发α节律、事件相关电位、锁相α节律和ERS/ERD。对多个α节律发生器的相干性和振幅的独立分析表明，模拟数据中的ERS/ERD主要是由刺激引起的多个α节律发生器之间相干性的变化引起的。非线性现象，如相位重置和α节律的携带与ERS/ERD背后的神经机制有关。Hum Brain Mapp, 2010。©2009 Wiley‐Liss, Inc。
In electroencephalographic (EEG) and magnetoencephalographic (MEG) signals, stimulus‐induced amplitude increase and decrease in the alpha rhythm, known as event‐related synchronization and desynchronization (ERS/ERD), emerge after a task onset. ERS/ERD is assumed to reflect neural processes relevant to cognitive tasks. Previous studies suggest that several sources of alpha rhythm, each of which can serve as an alpha rhythm generator, exist in the cortex. Since EEG/MEG signals represent spatially summed neural activities, ERS/ERD of the alpha rhythm may reflect the consequence of the interactions between multiple alpha rhythm generators. Two candidates modulate the magnitude of ERS/ERD: (1) coherence between the activities of the alpha rhythm generators and (2) mean amplitude of the activities of the alpha rhythm generators. In this study, we use a computational model of multiple alpha rhythm generators to determine the factor that dominantly causes ERS/ERD. Each alpha rhythm generator is modeled based on local column circuits in the primary visual cortex and made to interact with the neighboring generators through excitatory connections. We observe that the model consistently reproduces spontaneous alpha rhythms, event‐related potentials, phase‐locked alpha rhythms, and ERS/ERD in a specific range of connectivity coefficients. Independent analyses of the coherence and amplitude of multiple alpha rhythm generators reveal that the ERS/ERD in the simulated data is dominantly caused by stimulus‐induced changes in the coherence between multiple alpha rhythm generators. Nonlinear phenomena such as phase‐resetting and entrainment of the alpha rhythm are related to the neural mechanism underlying ERS/ERD. Hum Brain Mapp, 2010. © 2009 Wiley‐Liss, Inc.