Rumination syndrome the syndrome in mentally healthy patients appeared thereafter. At first, adult rumination was described and treated as a benign condition. It is now described as otherwise. While the base of patients to examine has gradually increased as more and more people come forward with their symptoms, awareness of the condition by the medical community and the general public is still limited. The chewing of cud by animals such as cows, goats, and giraffes is considered normal behavior. These animals are known as ruminants. Such behavior, though termed rumination, is not related to human rumination syndrome, but is ordinary. Involuntary rumination,
Retroperistalsis of humans are weak compared with those of most other mammals. In cud-chewing animals, such as cows, reverse peristalsis can occur so that the food is brought back from the stomach to the mouth for rechewing. When the stomach is filled, peristaltic waves are diminished. The presence of fat in a meal can completely stop these movements for a short period until it is diluted with gastric juices or removed from the stomach. Peristaltic waves start as weak contractions at the beginning of the stomach and progressively become stronger as they near the distal stomach regions. The waves help to