Short-term plasticity promotes synchronization of coupled chaotic oscillators in excitatory-inhibitory networks

Experimental and theoretical studies provided evidence that coordinated actions of excitation and inhibition (EI) are balanced by combinations of synaptic weights and synaptic plasticity. Nevertheless, whether the dynamic nature of individual cells significantly contributes to the emergence of spatiotemporal patterns under the consideration of short-term plasticity (STP) in neural networks is unclear and remains elusive. We present a coupled neural system of Hindmarsh-Rose neurons to understand the underlying mechanisms of irregular chaotic firing activities in tuning the interaction of EI balance and STP, thereby controlling the emergence of collective behaviors. Through synaptic weights tuning and STP for balancing the levels of excitation and inhibition, both EI networks of chaotic and nonchaotic cells with excitatory connections subject to STP produce a higher degree of synchronous firing patterns than those two EI networks without STP. Furthermore, the networks of chaotic cells produce complete synchronization more easily than the networks of nonchaotic cells under consideration of STP. The comparison with the results obtained in the networks of nonchaotic and chaotic cells implies that STP and synaptic weights are two ways of regulating the EI balance and, therefore, play a major but different role in the emergence of intermediate synchronous activities, coexisting multistable firing patterns, and complete synchronization.