论文标题
通过平均场神经网络中的时间变化来表征爆炸的表征
Characterization of blowups via time change in a mean-field neural network
论文作者
论文摘要
具有脉冲样相互作用的集成和开火神经元的理想化网络在平均场限制中遵守McKean-Vlasov扩散方程。这些方程很容易爆炸:对于足够强的相互作用耦合,在有限的时间内,相互作用的平均场相互作用差异有限,而神经元的有限分数同时尖峰,从而标记了宏观同步事件。在分析上表征这些爆炸奇点是理解平均场神经模型中尖峰同步的出现和持久性的关键。但是,这种分辨率受到经典考虑的动力学中平均场相互作用的第一阶段性质的阻碍。在这里,我们介绍了经典集成和火力动力学的延迟泊松变化,该动力学在平均场限制中在分析上得到很好的定义。尽管从根本上是非线性的,但我们表明,这种延迟的泊松动力学可以通过确定的时间变化转换为非相互作用的线性动力学。我们将这一次变化指定为通过续签第一组问题问题的非线性,延迟积分方程的解决方案。该公式还表明,可以通过关于时间变化的线性动力学的自洽,概率保存原理来确定同时尖峰神经元的比例。我们利用伴侣论文中提出的框架来分析显示具有足够大相互作用耦合的奇异平均场动力学的存在。
Idealized networks of integrate-and-fire neurons with impulse-like interactions obey McKean-Vlasov diffusion equations in the mean-field limit. These equations are prone to blowups: for a strong enough interaction coupling, the mean-field rate of interaction diverges in finite time with a finite fraction of neurons spiking simultaneously, thereby marking a macroscopic synchronous event. Characterizing these blowup singularities analytically is the key to understanding the emergence and persistence of spiking synchrony in mean-field neural models. However, such a resolution is hindered by the first-passage nature of the mean-field interaction in classically considered dynamics. Here, we introduce a delayed Poissonian variation of the classical integrate-and-fire dynamics for which blowups are analytically well defined in the mean-field limit. Albeit fundamentally nonlinear, we show that this delayed Poissonian dynamics can be transformed into a noninteracting linear dynamics via a deterministic time change. We specify this time change as the solution of a nonlinear, delayed integral equation via renewal analysis of first-passage problems. This formulation also reveals that the fraction of simultaneously spiking neurons can be determined via a self-consistent, probability-conservation principle about the time-changed linear dynamics. We utilize the proposed framework in a companion paper to show analytically the existence of singular mean-field dynamics with sustained synchrony for large enough interaction coupling.