1 Committee on Neurobiology, University of Chicago, 5801 S Ellis Ave, Chicago, IL 60637, USA.
2 Department of Neurology, Columbia University, New York 10032, NY, USA.
Int J Neural Syst. 2018 Dec;28(10):1850027. doi: 10.1142/S0129065718500272. Epub 2018 Jun 18.
During neocortical seizures in patients with epilepsy, microelectrode array recordings from the ictal core show a strong correlation between the fast, cellular spiking activities and the low-frequency component of the potential field, reflected in the electrocorticogram (ECoG). Here, we model the relationship between the cellular spike activity and this low-frequency component as the input and output signals of a linear time invariant system. Our approach is based on the observation that this relationship can be characterized by a so-called sinc function, the unit impulse response of an ideal (brick-wall) filter. Accordingly, using a brick-wall filter, we are able to convert ictal cellular spike inputs into an output that significantly correlates with the observed seizure activity in the ECoG , while ECoG recordings of subsequent seizures within patients also show significant, but lower, correlations . Furthermore, we can produce seizure-like output signals using synthetic spike trains with ictal properties. We propose a possible physiological mechanism to explain the observed properties associated with an ideal filter, and discuss the potential use of our approach for the evaluation of anticonvulsant strategies.
在癫痫患者的大脑皮层癫痫发作期间，来自发作核心的微电极阵列记录显示，快速的细胞尖峰活动与潜在场的低频分量之间存在很强的相关性，这反映在脑电图（ECoG）中。在这里，我们将细胞尖峰活动与这个低频分量之间的关系建模为线性时不变系统的输入和输出信号。我们的方法基于这样一个观察结果，即这种关系可以用所谓的 sinc 函数来描述，这是理想（砖墙）滤波器的单位脉冲响应。因此，使用砖墙滤波器，我们能够将发作期的细胞尖峰输入转换为与 ECoG 中观察到的癫痫活动显著相关的输出，而患者后续发作的 ECoG 记录也显示出显著但较低的相关性。此外，我们可以使用具有发作特性的合成尖峰序列产生类似发作的输出信号。我们提出了一种可能的生理机制来解释与理想滤波器相关的观察到的特性，并讨论了我们的方法在评估抗惊厥策略中的潜在用途。
