The enteric nervous system (ENS) is a complex network of neurons embedded within the wall of the gastrointestinal tract and is often referred to as the “brain of the gut.” It regulates essential digestive functions including motility, secretion, blood flow, and interactions with the immune system. Unlike other peripheral neural networks, the ENS is capable of autonomous activity independent of central nervous system input, while still maintaining bidirectional communication with the brain. This article reviews the anatomical organization, physiological functions, and integrative role of the enteric nervous system in gastrointestinal regulation. Understanding ENS physiology is fundamental for explaining normal digestive function and the pathophysiology of gastrointestinal disorders.

Enteric nervous system; gastrointestinal physiology; gut–brain axis; motility; secretion; neurogastroenterology

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