Glossary · Y học
Enteric nervous system
The network of neurons within the wall of the digestive tract that controls gastrointestinal activity. In humans it contains roughly 200–600 million neurons, enough to be sometimes called a "second brain"; it works with the central nervous system but can control many digestive processes fairly independently.
The digestive system is innervated both through its connections with the central nervous system and by the enteric nervous system within the wall of the gastrointestinal tract. According to Furness (2014), the enteric nervous system works in concert with the reflex and command centres of the central nervous system, and with neural pathways passing through sympathetic ganglia, to control digestive function; information flows in both directions between the enteric and central nervous systems.
In humans, the enteric nervous system contains 200–600 million neurons, distributed across many thousands of small ganglia, most of which are found in two plexuses: the myenteric and the submucosal. The myenteric plexus forms a continuous network running from the upper oesophagus downward.
Its large neuron count and integrated circuits let it regulate many gut processes fairly autonomously, which is why it is sometimes called a "second brain". Even so, the extent to which the enteric or the central nervous system controls digestion varies considerably along the digestive tract.