Influence of synaptic interaction on firing synchronization and spike death in excitatory neuronal networks

TL;DR

This paper explores how strong excitatory synaptic interactions can induce spike death, reducing synchronization in neuronal networks by disrupting neuron oscillation feedback mechanisms.

Contribution

It reveals the phenomenon of spike death caused by high efficacy synaptic interactions and its impact on network synchronization, a novel insight into neuronal dynamics.

Findings

Spike death occurs under high efficacy excitatory synaptic perturbation.

Spike death reduces network synchronization and makes it less sensitive to neuron heterogeneity.

Transition to fixed points disrupts rhythmic adjustment, preventing increased synchronization.

Abstract

We investigated the influence of efficacy of synaptic interaction on firing synchronization in excitatory neuronal networks. We found spike death phenomena, namely, the state of neurons transits from limit cycle to fixed point or transient state. The phenomena occur under the perturbation of excitatory synaptic interaction that has a high efficacy. We showed that the decrease of synaptic current results in spike death through depressing the feedback of sodium ionic current. In the networks with spike death property the degree of synchronization is lower and unsensitive to the heterogeneity of neurons. The mechanism of the influence is that the transition of neuron state disrupts the adjustment of the rhythm of neuron oscillation and prevents further increase of firing synchronization.