Algonquin College
13.4 - Nervous Control of Digestion
There are two separate nervous controls of digestion: the intrinsic and extrinsic nerve plexuses.

Intrinsic plexuses

The intrinsic nerve plexuses of the digestive system are collectively called the enteric nervous system. These nerve plexuses function independently of the central nervous system, controlling digestive function in response to stimuli inside the digestive tract.

There are two intrinsic nerve plexuses that control the short reflexes of the digestive system: Extrinsic plexuses

The extrinsic nerve plexuses control the long reflexes of the digestive system. The long reflexes involve the central nervous system and nerves of the autonomic nervous system. The extrinsic nerve plexuses control digestive responses from outside the digestive system such as emotion and information about food from the special senses (sight, smell, taste). The extrinsic nerves come from both branches of the ANS (sympathetic and parasympathetic) and alter the activity of the intrinsic plexuses, hormone secretion or directly stimulate or inhibit smooth muscles and glands.

The extrinsic inputs from the two branches of the ANS have different effects on the digestive system: Control of gastric secretions

Secretions of the stomach are controlled in three separate phases:

Cephalic phase Gastric phase Intestinal phase