Abstract
Using phase response curves and averaging theory, we derive phase oscillator models for the lamprey central pattern generator from two biophysically-based 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 network-based model can also easily produce approximately constant phase lags along the spinal cord, as observed experimentally. Precise control of phase lags in the network-based 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 network-based models approach the determinisitic model as the number of connections increases.

















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Acknowledgements
This work was supported by NSF EF-0425878 and NIH NS054271. PV was supported by Imre Korányi and Zoltán Magyary fellowships as well as by OTKA-72368, and hosted by the Program in Applied and Computational Mathematics of Princeton University. KH was supported by NSF DMS-0624024, and hosted by the Department of Biology, University of Maryland College Park. KH also gratefully acknowledges the computing resources of the Department of Mathematics and Statistics at University of Maryland Baltimore County.
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Várkonyi, P.L., Kiemel, T., Hoffman, K. et al. On the derivation and tuning of phase oscillator models for lamprey central pattern generators. J Comput Neurosci 25, 245–261 (2008). https://doi.org/10.1007/s10827-008-0076-8
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DOI: https://doi.org/10.1007/s10827-008-0076-8