Synchronization of Neocortical Interneurons
As shown by recent experiments, the Fast-Spiking inhibitory interneurons of the neocortex interact also by electrical synapses (gap-junctions). Moreover, their synchronous discharge enhances their inhibitory control of pyramidal neurons. By using a biophysical model of these interneurons the synchronization properties of a network of two synaptically coupled units are investigated: in the presence only of inhibitory coupling, well defined regions exist in the space of strength and duration of the synaptic current, where synchronous regimes occur. When electrical synapses are included, the region of synchronous discharge becomes larger. In both cases the coherent states are characterized by discharge frequencies in the gamma range. Lastly, the effects of heterogeneity obtained by using either different stimulation currents or unidirectional inhibitory coupling, are studied.
KeywordsSpike Train Inhibitory Interneuron Electrical Coupling Inhibitory Synapse Coherence Measure
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