| The stomatogastric ganglion is one of the most thoroughly studied neural networks, consisting only of about thirty neurons located on the stomachs of crustaceans like lobsters. The ganglion functions based upon central pattern generators (CPGs), which are neural networks that are capable of forming rhythmically-patterned motor responses. In the case of the stomatogastric ganglion, the two CPGs are the pyloric and gastric mill;
this website chronicles the simulation of the pyloric circuit
as well as the effect of dopamine on that circuit using the neural network simulation provided by Izekevich. The role of the pyloric network is to create a three-phase pattern that is used to constrict and dilate the striated muscles of the crustacean stomach.
The nervous system of a crustacean consists of commissural
ganglia, the esophageal ganglion, the stomatogastric ganglion,
and the nerves connecting these ganglia. This is the reason
why such systems are chosen: they are infinitely simpler than
the more complex human system. What’s more, though the
stomatogastric system is internal, it actually helps
researches examine the role of the nervous system in
determining rhythmic motor patterns (like walking for
example), because the foregut of crustaceans is derived from
the ectoderm and consists of striated muscle, similar to the
tissue that makes up the limbs of those same crustaceans.
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