A phase sensitivity based method for prediction of modes of behavior in quadrupedal locomotion
DeFranceschi, Anton Allan
Clark, John W., Jr.
Master of Science
The objective of this study is development of prediction methods for characterizing the electrical behavior of ring type central pattern generators (CPGs). A mathematical model of the prototypical bursting neuron R15 from the abdominal ganglion of Aplysia is used, along with a simple model of the inhibitory synapse, to form a four neuron ring model of a CPG. The basic mode of a four neuron ring CPG model is able to characterize the walk, trot and bound gaits associated with quadrupedal locomotion. The phase sensitivity of neuron R15 to an external input is investigated, and the results are expressed in terms of cophase curves that are used to formulate prediction algorithms for the behavior of ring type networks. These prediction algorithms are utilized in a Network Emulator that provides an accurate simulation of the behavior of the ring type networks at a considerable savings in computation time compared with numerical solutions of the ordinary differential equations associated with these networks. We further extend this work by examining the conditions for control of the modes of three and four neuron ring CPGs by external stimuli.