Esophageal physiology: normal and abnormal motor function.

The physiological controls of esophageal motor function are complex. Despite the relatively simple-appearing contraction waves of the esophagus compared with other gastrointestinal organs, the fascinating interaction of the CNS with the nerve cells in the esophagus itself has delayed complete understanding of esophageal peristalsis. The list of recognized modulating influences, particularly on the smooth muscle components, continues to expand. Although there are many studies concerning normal esophageal motor function, the pathophysiological mechanisms of motor dysfunction in many of the common motility disorders remain obscure.