An effect of afferent stimulation using a hardware model of a central pattern generator based on neuronal networks

This paper introduces hardware designs for a half-centered locomotor central pattern generator (CPG), composed of units reproducing the electrical behavior of neurons and synapses, such as action potentials, bursting discharges, and post-synaptic potentials. A typical phenomenon generated by the CPG is an alternating rhythmic activity of extensor and flexor sites, in the absence of external rhythmic input. In order to reproduce the phase resetting and non-resetting rhythmic activities observed after the afferent stimulation, a two-level CPG network and unit burst generators were proposed by Rybak et al. from an approach based on mathematical modeling. This paper confirms that such phase resetting and non-resetting rhythmic phenomena could be well reproduced by the hardware design of a two-level CPG using the electronic circuit simulator SPICE. In particular, it has been clarified that the phase resetting depends on the amount of stimulation of the extensor afferents during extension.