Gastrocolic reflex
The gastrocolic reflex or gastrocolic response is one of a number of physiological reflexes controlling the motility, or peristalsis, of the gastrointestinal tract. It involves an increase in motility of the colon in response to stretch in the stomach and byproducts of digestion in the small intestine. Thus, this reflex is responsible for the urge to defecate following a meal. The small intestine also shows a similar motility response. The gastrocolic reflex helps make room for more food.