Shirani Farshad
Department of Mathematics and Statistics, Georgetown University, Washington, DC, 20057, USA.
J Comput Neurosci. 2020 Feb;48(1):103-122. doi: 10.1007/s10827-019-00738-0. Epub 2020 Jan 28.
In this paper a mean field model of spatio-temporal electroencephalographic activity in the neocortex is used to computationally study the emergence of neocortical gamma oscillations as a result of neuronal response modulation. It is shown using a numerical bifurcation analysis that gamma oscillations emerge robustly in the solutions of the model and transition to beta oscillations through coordinated modulation of the responsiveness of inhibitory and excitatory neuronal populations. The spatio-temporal pattern of the propagation of these oscillations across the neocortex is illustrated by solving the equations of the model using a finite element software package. Thereby, it is shown that the gamma oscillations remain localized to the regions of neuronal modulation. Moreover, it is discussed that the inherent spatial averaging effect of commonly used electrocortical measurement techniques can significantly alter the amplitude and pattern of fast oscillations in neocortical recordings, and hence can potentially affect physiological interpretations of these recordings.
在本文中，一个新皮层时空脑电图活动的平均场模型被用于通过计算研究由于神经元反应调制而出现的新皮层伽马振荡。使用数值分岔分析表明，伽马振荡在模型解中稳健出现，并通过抑制性和兴奋性神经元群体反应性的协同调制转变为贝塔振荡。通过使用有限元软件包求解模型方程，说明了这些振荡在新皮层中传播的时空模式。由此表明，伽马振荡仍局限于神经元调制区域。此外，还讨论了常用的皮层电测量技术固有的空间平均效应会显著改变新皮层记录中快速振荡的幅度和模式，因此可能会影响对这些记录的生理学解释。
