Chapter 19 Influence of the Microbiota on the Development and Function of the “Second Brain”—The Enteric Nervous System

The enteric nervous system (ENS) is the intrinsic nervous system of the gut, made up of an extensive network of neurons that lines the walls of the gastrointestinal (GI) tract. The framework of the ENS is laid during the first gestational trimester, but the network continues to undergo modifications throughout the prenatal period and into postnatal life. Colonization of the GI tract by trillions of microorganisms during the early postnatal …