Divisive inhibition enhances entrainment and long-range synchronization in a neural mass model

The ability of neural networks to be entrained to different frequencies characterizes the functional flexibility and adaptability of the networks. Also the phenomenon of long-range synchronization between two local networks is crucial for cognitive functions. Previous work explored the influence of network structure and local dynamics on these phenomena but the influence of divisive inhibition (gain control) was never investigated. A neural mass model of a neocortical local network which includes soma-targeting and dendrite-targeting interneuronal populations was used to investigate the role of divisive inhibition in entrainment and long-range synchronization. The results demonstrate that the presence of divisive inhibition in the local network enable the entrainment to a wider range of frequencies and improves the synchronization between two local networks. The mechanism of divisive inhibition, which is predominantly provided by the soma-targeting interneurons, is suggested to be the link between molecular alterations in soma-targeting interneurons and deficiencies in long-range synchronization in the pathology of schizophrenia.