Spontaneous spiking in an autaptic Hodgkin-Huxley set up

TL;DR

This paper investigates how intrinsic channel noise affects the spontaneous spiking behavior of a neuron with autaptic feedback using a stochastic Hodgkin-Huxley model, revealing delay-induced bursting and frequency-locking phenomena.

Contribution

It introduces a stochastic Hodgkin-Huxley model with delayed feedback to analyze the effects of intrinsic noise on neuronal spiking behavior, highlighting new delay-induced dynamics.

Findings

Delay induces bursting and multimodal interspike interval distributions.

Spontaneous activity is reduced at characteristic frequencies due to delay.

Frequency-locking mechanisms are observed in the mean interspike interval.

Abstract

The effect of intrinsic channel noise is investigated for the dynamic response of a neuronal cell with a delayed feedback loop. The loop is based on the so-called autapse phenomenon in which dendrites establish not only connections to neighboring cells but as well to its own axon. The biophysical modeling is achieved in terms of a stochastic Hodgkin-Huxley model containing such a built in delayed feedback. The fluctuations stem from intrinsic channel noise, being caused by the stochastic nature of the gating dynamics of ion channels. The influence of the delayed stimulus is systematically analyzed with respect to the coupling parameter and the delay time in terms of the interspike interval histograms and the average interspike interval. The delayed feedback manifests itself in the occurrence of bursting and a rich multimodal interspike interval distribution, exhibiting a delay-induced reduction of the spontaneous spiking activity at characteristic frequencies. Moreover, a specific frequency-locking mechanism is detected for the mean interspike interval.