Effects of Neural Heterogeneity on Spiking Neural Network Dynamics

Abstract

The brain is composed of complex networks of interacting neurons that express considerable heterogeneity in their physiology and spiking characteristics. How does neural heterogeneity affect macroscopic neural dynamics and how does it contribute to neurodynamic functions? In this letter, we address these questions by studying the macroscopic dynamics of networks of heterogeneous Izhikevich neurons. We derive mean-field equations for these networks and examine how heterogeneity in the spiking thresholds of Izhikevich neurons affects the emergent macroscopic dynamics. Our results suggest that the level of heterogeneity of inhibitory populations controls resonance and hysteresis properties of systems of coupled excitatory and inhibitory neurons. Neural heterogeneity may thus serve as a means to control the dynamic repertoire of mesoscopic brain circuits.

Intrinsic neural diversity quenches the dynamic volatility of neural networks

“…and echoes numerous previous studies on heterogeneous networks [43,47,49,50,72]. This heterogeneity leads to differing response functions for the individual neurons (Fig.…”

“…This also holds true for process that continuously change the brain during development and ageing, where brain dynamics remain stable over many decades despite the structural changes that accompany time, and pathological processes, where failure to regulate brain activity in the face of pathological insults predispose the brain to dynamic volatility [18,21]. A confluence of both experimental [1,4,25,[38][39][40][41][42][43] and theoretical studies [43][44][45][46][47][48][49][50] have highlighted the role of heterogeneity in brain dynamics and stability. Notably, phenotypic diversity has been shown to promote the stability of brain function and its associated dynamics through degeneracy, redundancy and covariation [1,25,100].…”

“…These questions have been examined by neuroscientists as well: numerous experimental [1,4,25,[38][39][40][41][42][43] and theoretical [43][44][45][46][47][48][49][50] studies have explored the influence of cellular heterogeneity, seemingly the norm in the brain [51][52][53][54][55][56], on neural dynamics and communication. Furthermore in the context of disease states, excitability heterogeneity can stabilize neural dynamics away from pathological brain states [43].…”

The tuning of tuning: how adaptation influences single cell information transfer

“…The heterogeneity of neuron properties has received much interest lately: for instance, it has been shown that heterogeneity in neural populations can increase coding robustness and efficiency [47], help optimize information transmission [48], increase network responsiveness [49], promote robust learning [50], help to control the dynamic repertoire of neural populations [51] and improve the performance on several tasks [52, 53]. Here, we show that in particular, the population of excitatory neurons of the barrel cortex shows a large variability in their intrinsic and response properties.…”