Enhanced vibrational resonance in a single neuron with chemical autapse for signal detection*

Abstract

Many animals can detect the multi-frequency signals from their external surroundings. The understanding for underlying mechanism of signal detection can apply the theory of vibrational resonance, in which the moderate high frequency driving can maximize the nonlinear system’s response to the low frequency subthreshold signal. In this work, we study the roles of chemical autapse on the vibrational resonance in a single neuron for signal detection. We reveal that the vibrational resonance is strengthened significantly by the inhibitory autapse in the neuron, while it is weakened typically by the excitatory autapse. It is generally believed that the inhibitory synapse has a suppressive effect in neuronal dynamics. However, we find that the detection of the neuron to the low frequency subthreshold signal can be improved greatly by the inhibitory autapse. Our finding indicates that the inhibitory synapse may act constructively on the detection of weak signal in the brain and neuronal system.