Abstract:

The mechanism of signal perception in the nervous system is highly complex and heavily dependent on environmental factors. One of the most significant factors affecting this mechanism is the naturally emerging noise at both the micro and macro levels of the brain. Experimental and numerical studies demonstrate that the nervous system utilizes noise to optimize its information processing capacity. Maximizing the weak signal capacity of neurons at a sufficient noise level is explained with the concept of “stochastic resonance”. This study examines the effects of weak signal frequency on the stochastic resonance phenomenon triggered by ion channel noise depending on the biological functions of the feedback mechanism in Hodgkin-Huxley neurons with an electrical feedback connection. The findings indicate that the autaptic feedback mechanism significantly enhances the signal coding capacity of Hodgkin-Huxley neurons across all frequencies within the range of frequencies to which the neuron is sensitive. Also, it is observed that the subthreshold signal detection capacity of Hodgkin-Huxley neurons exhibits resonance behaviour depending on feedback coupling strength at the appropriate feedback time delays for all frequencies in this range. Furthermore, it is shown that the maximal weak signal coding performance of Hodgkin-Huxley neuron displays multiple stochastic resonance phenomena depending on the feedback time delay. These points of maximal stochastic resonance are determined by the frequency of the applied weak signal.