Fast Response and Temporal Coding on Coherent Oscillations in Small-World Networks

TL;DR

This study demonstrates that small-world network topologies enable rapid responses, coherent oscillations, and effective temporal coding in neuron networks, combining advantages of regular and random connectivities in a biologically plausible manner.

Contribution

It is the first to show that small-world connectivity is essential for achieving fast, coherent, and temporally coded neural dynamics simultaneously.

Findings

Random networks respond quickly but lack coherence.

Regular networks show coherence but are slow.

Small-world networks combine speed, coherence, and temporal coding.

Abstract

We have investigated the role that different connectivity regimes play on the dynamics of a network of Hodgkin-Huxley neurons by computer simulations. The different connectivity topologies exhibit the following features: random connectivity topologies give rise to fast system response yet are unable to produce coherent oscillations in the average activity of the network; on the other hand, regular connectivity topologies give rise to coherent oscillations and temporal coding, but in a temporal scale that is not in accordance with fast signal processing. Finally, small-world (SW) connectivity topologies, which fall between random and regular ones, take advantage of the best features of both, giving rise to fast system response with coherent oscillations along with reproducible temporal coding on clusters of neurons. Our work is the first, to the best of our knowledge, to show the need for a small-world topology in order to obtain all these features in synergy within a biologically plausible time scale.