Firing regulation of fast-spiking interneurons by autaptic inhibition

Abstract

Fast-spiking (FS) interneurons in the brain are self-innervated by powerful inhibitory GABAergic autaptic connections. By computational modelling, we investigate how autaptic inhibition regulates the firing response of such interneurons. Our results indicate that autaptic inhibition both boosts the current threshold for action potential generation as well as modulates the input-output gain of FS interneurons. The autaptic transmission delay is identified as a key parameter that controls the firing patterns and determines multistability regions of FS interneurons. Furthermore, we observe that neuronal noise influences the firing regulation of FS interneurons by autaptic inhibition and extends their dynamic range for encoding inputs. Importantly, autaptic inhibition modulates noise-induced irregular firing of FS interneurons, such that coherent firing appears at an optimal autaptic inhibition level. Our result reveal the functional roles of autaptic inhibition in taming the firing dynamics of FS interneurons.

Dendritic and Axonal Propagation Delays Determine Emergent Structures of Neuronal Networks with Plastic Synapses

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Stimulus-induced Epileptic Spike-Wave Discharges in Thalamocortical Model with Disinhibition

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Different dynamical behaviors induced by slow excitatory feedback for type II and III excitabilities

“…For example, different biophysical basis such as internal and external currents and dynamical behaviors to sustained stimulations of three types of excitability have been identified 6,7 . The transition between types of excitability can be induced by changes of ionic currents 6,[11][12][13] , external synaptic inputs 7 , and autaptic currents 15,16 . There have been many investigations of the physiological significance 6,7,14 and dynamics 11,15,[17][18][19][20] of different excitabilities.…”

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