Kathleen A. Hoffman


On the derivation and tuning of phase oscillator models for lamprey central pattern generators Peter L. Varkonyi, Tim Kiemel, Kathleen Hoffman, Avis H. Cohen and Philip Holmes Abstract: Using phase response curves (PRCs) and averaging theory, we derive phase oscillator models for the lamprey central pattern generator from two biophysicallybased segmental models. The first one relies on network dynamics within a segment to produce the rhythm, while the second contains bursting cells. We study intersegmental coordination and show that the former class of models shows more robust behavior over the animal's range of swimming frequencies. The networkbased model can also easily produce approximately constant phase lags along the spinal cord, as observed experimentally. Precise control of phase lags in the networkbased model is obtained by varying the relative strengths of its six different connection types with distance in a phase model with separate coupling functions for each connection type. The phase model also describes the effect of randomized connections, accurately predicting how quickly random networkbased models approach the determinisitic model as the number of connections increases. 
