Journal of Computational Neuroscience

, Volume 22, Issue 1, pp 21–38 | Cite as

Systems-level modeling of neuronal circuits for leech swimming

  • M. Zheng
  • W. O. Friesen
  • T. Iwasaki


This paper describes a mathematical model of the neuronal central pattern generator (CPG) that controls the rhythmic body motion of the swimming leech. The systems approach is employed to capture the neuronal dynamics essential for generating coordinated oscillations of cell membrane potentials by a simple CPG architecture with a minimal number of parameters. Based on input/output data from physiological experiments, dynamical components (neurons and synaptic interactions) are first modeled individually and then integrated into a chain of nonlinear oscillators to form a CPG. We show through numerical simulations that the values of a few parameters can be estimated within physiologically reasonable ranges to achieve good fit of the data with respect to the phase, amplitude, and period. This parameter estimation leads to predictions regarding the synaptic coupling strength and intrinsic period gradient along the nerve cord, the latter of which agrees qualitatively with experimental observations.


Central pattern generator Locomotion Weakly coupled oscillator Neuronal oscillator Modeling Systems approach 


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© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  1. 1.Department of Mechanical and Aerospace EngineeringUniversity of VirginiaCharlottesvilleUSA
  2. 2.Department of BiologyUniversity of VirginiaCharlottesvilleUSA

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