Stomatogastric nervous system

Definition

A discrete neural network in arthropods that innervates the foregut and midgut, comprising the stomatogastric ganglion, oesophageal ganglion, and paired commissural ganglia. The STNS functions as a central pattern generator that coordinates rhythmic muscular contractions of the gut for feeding and digestion, and has become a foundational model system in neuroethology due to its small, identified, and electrophysiologically accessible neurons.

Etymology

From Greek stoma (mouth) + gaster (stomach/belly), referring to its innervation of the foregut region between mouth and stomach.

Example

In the spiny lobster Panulirus interruptus, the stomatogastric nervous system generates two distinct motor rhythms—one for the gastric mill teeth and another for the pyloric filter—allowing researchers to study how neuromodulators reconfigure the same circuit for different behaviors.

Synonyms

• STNS

Related Terms

• stomatogastric ganglion
• central pattern generator
• oesophageal ganglion
• commissural ganglion
• enteric nervous system
• neuroethology

Usage Notes

The abbreviation STNS is standard in the literature; contrast with the 'stomatogastric ganglion' (STG), which is only one component. The STNS is distinct from the visceral nervous system in vertebrates and should not be confused with the enteric nervous system of mammals, though both control gut motility. Most detailed work has been done in decapod crustaceans, but homologous systems occur across insects and other arthropods with variable ganglionic fusion patterns.