Modulation of excitatory synaptic coupling facilitates synchronization and complex dynamics in a nonlinear model of neuronal dynamics
We study dynamical synchronization in a model of a neural system constituted by local networks of densely interconnected excitatory and inhibitory neurons. Neural dynamics are determined by voltage- and ligand-gated ion channels. Coupling between the local networks is introduced via sparse excitatory connectivity. With modulation of this long-range synaptic coupling the system undergoes a transition from independent oscillations to chaotic synchronization. Between these states exists a 'weakly stable state with epochs of synchronization and complex intermittent desynchronization. This may facilitate adaptive brain function by engendering a diverse repertoire of dynamics and contribute to the genesis of complexity in the EEG.
synchronization intermittency neuromodulation