Propagation effect of the thalamic feed-forward and feed-back inhibition in multi-type coupling models

Seizure waves of epilepsy can propagate in a coupled thalamocortical model, which typically occurs in malfunctioning neuronal networks. However, it remains unclear whether thalamic feed-forward inhibition (FFI) and feed-back inhibition (FBI), the two most important microcircuits in this network, have propagation effects. In this study, we first investigated the importance of the pyramidal neuronal population-thalamic reticular nucleus and specific relay nucleus-thalamic reticular nucleus pathways in the Taylor model for seizure control as FFI and FBI, respectively. Subsequently, using the FBI as a crucial parameter, we constructed 2- and 3-compartment coupling models and evaluated their impact on seizure propagation in other chambers by varying the degree of coupling strength. Finally, we replicated the above study in a 10-compartment model to ensure the robustness of the findings. We confirmed that FBI is more effective by analyzing the combined effect of FFI and FBI, and the pathology state does advance as the coupling strength is increased. These findings elucidate the roles that these two pathways play in the propagation of epileptic seizures and may offer fresh perspectives on the clinical management of epilepsy.