A VLSI circuit of lamprey unit pattern generator

The purpose of this research is to develop an analog VLSI electronic circuit that mimics the behavior of the biological lamprey spinal cord. The lamprey is an eel-like lower vertebrate with a relatively simple nervous system. The pattern generator for locomotion is distributed along the 100 spinal segments of the lamprey spinal cord and can be treated as a chain of coupled unit pattern generators (uPG) with oscillatory properties. In this work we consider a 4 neuron uPG model. Bifurcation analysis of this model indicates a wide range of behaviors. In addition, a CMOS analog integrated circuit has been designed, fabricated and tested which models the biological lamprey unit pattern generator. Measurement results show that the electronic circuit behavior is qualitatively similar to that of the numerical model