Coupling-Excitability Correlation Shapes Macroscopic Dynamics in a Network of Theta Neurons

Correlations between neuronal excitability and synaptic coupling are biologically grounded yet remain underexplored in theoretical models. Here, we show that embedding such structured correlations in a network of Theta neurons, analyzed through the Ott-Antonsen reduction, induces multi-window bistability, firing clusters, and distinct routes to chaos. Localized suppressive effects, arising without explicitly designated inhibitory units, reshape macroscopic dynamics through clustering patterns and attractor switching. These results highlight correlation geometry as a small yet powerful organizing principle, linking microstructural diversity to emergent dynamical complexity in large-scale excitable systems, with implications for understanding structure-function relationships beyond neural circuits.