Emergent gamma synchrony in all-to-all interneuronal networks

Area of Science:

• Neuroscience
• Computational Neuroscience
• Systems Neuroscience

Background:

• Neural synchronization is crucial for information processing in the brain.
• Heterogeneous networks of inhibitory interneurons are fundamental components of neural circuits.
• Spike timing dependent plasticity (STDP) is a key mechanism for synaptic modification.

Purpose of the Study:

• To investigate the role of STDP in the emergence of in-phase synchronization in heterogeneous networks of coupled inhibitory interneurons.
• To understand how STDP shapes network structure and information flow.
• To assess the generalizability of STDP-induced synchronization in larger neural networks.

Main Methods:

• Utilized a computational model of two mutually coupled interneurons (2-MCI) with STDP.
• Analyzed network dynamics, including synchronization states and synaptic plasticity.
• Extended the findings to a larger Wang-Buzsaki network (100-MCI) with all-to-all coupling.

Main Results:

• STDP promotes stable 1:1 in-phase synchronization and higher-order synchronization states in the 2-MCI network.
• Synchronization leads to asymmetric synaptic potentiation (high-frequency neurons) and de-potentiation (low-frequency neurons).
• This asymmetry establishes directed information flow from low- to high-frequency firing neurons.
• STDP facilitates robust synchronization in larger networks across a wider range of neuronal heterogeneity.

Conclusions:

• STDP at inhibitory synapses is a viable mechanism for generating robust neural synchronization.
• Synaptic plasticity dynamically shapes network connectivity to support synchronized activity.
• The findings provide insights into how neural circuits achieve coordinated function despite intrinsic variability.