Spatio-temporal activity patterns induced by triadic interactions in an in silico neural medium

TL;DR

This study explores how triadic interactions in a simulated neural network lead to diverse spatio-temporal activity patterns, revealing complex dynamics such as propagation waves and up/down state transitions.

Contribution

It introduces a detailed analysis of emergent activity patterns in an in silico neural medium with triadic interactions, linking these to triadic percolation models.

Findings

Different activity phases emerge depending on interaction parameters.

Propagation of activity waves occurs in high-activity states.

The model exhibits up/down state-like switching behavior.

Abstract

Triadic interactions are general mechanisms by which a node or neuron can regulate directly the link or synapse between other two neurons. The regulation takes place in a familiar way by either depressing or facilitating synaptic transmission. Such interactions are ubiquitous in neural systems, accounting for axo-axonic synapses and tripartite synapses mediated by astrocytes, for instance, and have been related to neuronal and synaptic processes at different time-scales, including short and long-term synaptic plasticity. In the field of network science, triadic interactions have been shown to produce complex spatio-temporal patterns of connectivity. Here, we investigate the emergent behavior of an in silico neural medium constituted by a population of leaky integrate-and-fire neurons with triadic interactions. We observe that, depending on relevant parameters defining triadic interactions, different activity patterns emerge. These include i) a silent phase, ii) a low-activity phase in which complex spatio-temporal patterns of low neuronal firing rate emerge that propagate through the medium, iii) a high-activity phase characterized by complex spatio-temporal patterns of high neuronal firing rate that propagate through the neural medium as waves of high firing activity over a bulk of low activity neurons, and iv) a pseudo-blinking phase in which the neural medium switches between high and low activity states, in a similar fashion to up/down state transitions. Here we analyse in depth the features of such patterns and relate our findings to the recently proposed model of triadic percolation.