Experimental active spike responses of analog electrical neuron: beyond ``integrate-and-fire'' transmission

Using an analog electrical FitzHugh-Nagumo neuron including complex threshold excitation (CTE) properties, we analyze its spiking responses on pulse stimulation. The system is subjected to external pulse stimulus and can generate nonlinear integrate-and-fire and resonant responses which are typical for excitable neuronal cells. Following earlier theoretical predictions, we found that for certain parameters range, there is a possibility to trigger a spiking sequence with a finite number of spikes in response to a single short stimulus pulse. Hence, active transformation of N incoming pulses to M outgoing spikes is possible. We also show that the nonlinear electrical circuit with the CTE feature can be effectively synchronized by a periodic pulse train with 1 to M spike frequency ratio.