[4][5] The enteric nervous system is capable of operating independently of the brain and spinal cord,[6] but is thought to rely on innervation from the vagus nerve and prevertebral ganglia in healthy subjects.

However, vertebrate studies show that when the vagus nerve is severed, the enteric nervous system continues to function.

[7] In vertebrates, the enteric nervous system includes efferent neurons, afferent neurons, and interneurons, all of which make the enteric nervous system capable of carrying reflexes and acting as an integrating center in the absence of CNS input.

The enteric nervous system also makes use of more than 30 neurotransmitters, most of which are identical to the ones found in CNS, such as acetylcholine, dopamine, and serotonin.

[18][19][20] The enteric nervous system has the capacity to alter its response depending on such factors as bulk and nutrient composition.

The secretion of gastrointestinal hormones, such as gastrin and secretin, is regulated through cholinergic neurons residing in the walls of the digestive tract.

Hormone secretion is controlled by the vagovagal reflex, where the neurons in the digestive tract communicate through both afferent and efferent pathways with the vagus nerve.

Specifically, neurogastroenterology focuses on the functions, malfunctions, and the malformations of the sympathetic, parasympathetic, and enteric divisions of the digestive tract.

[25] The term also describes a medical sub-specialism of gastroenterology dedicated to the treatment of motility and functional gastrointestinal disorders.

Clinical research in neurogastroenterology focuses mainly on the study of common motility disorders such as gastroesophageal reflux disease, the damage of the mucosa of the esophagus caused by rising stomach acid through the lower esophageal sphincter.

[28] Transplantation, previously described as a theoretical possibility,[29] has been a clinical reality in the United States since 2011 and is regularly performed at some hospitals.