Analog circuit model of lamprey unit pattern generator

Neural circuitry within the spinal cord of the lamprey, a primitive vertebrate, can generate self-sustained oscillations for locomotion (swimming). This pattern generator can be modeled as a chain of oscillatory unit pattern generator segments. In this paper, the design and implementation of an analog electronic circuit which mimics the behavior of such a unit pattern generator of the lamprey is presented. The circuitry mimics a neural network containing 6 neurons with simplified biophysical properties. The analog circuit is capable of generating stable oscillatory output at different frequencies with the appropriate phase relationships among the different neural outputs. This work is the first in a series of circuits designed to have possible applications in neuroscience research and in the development of artificial locomotor systems.