Synaptic Plasticity and Spike Synchronisation in Neuronal Networks

TL;DR

This paper reviews how synaptic plasticity influences the topology and synchronization of neuronal networks, highlighting the role of excitation-inhibition balance and noise in shaping brain-like structures.

Contribution

It demonstrates the impact of synaptic strength ratios on network topology and synchronization in Hodgkin-Huxley neuron models, revealing mechanisms underlying brain-like connectivity.

Findings

Evolved network topology depends on inhibitory/excitatory ratio.

Rich-club phenomenon emerges with balanced excitation and inhibition.

Noise enhances synaptic strength and influences network synchronization.

Abstract

Brain plasticity, also known as neuroplasticity, is a fundamental mechanism of neuronal adaptation in response to changes in the environment or due to brain injury. In this review, we show our results about the effects of synaptic plasticity on neuronal networks composed by Hodgkin-Huxley neurons. We show that the final topology of the evolved network depends crucially on the ratio between the strengths of the inhibitory and excitatory synapses. Excitation of the same order of inhibition revels an evolved network that presents the rich-club phenomenon, well known to exist in the brain. For initial networks with considerably larger inhibitory strengths, we observe the emergence of a complex evolved topology, where neurons sparsely connected to other neurons, also a typical topology of the brain. The presence of noise enhances the strength of both types of synapses, but if the initial network has synapses of both natures with similar strengths. Finally, we show how the synchronous behaviour of the evolved network will reflect its evolved topology.