There are many more factors that account for a feeling of satiety than food lingering in the stomach. Glucose levels could account for satiety, as well as other factors. Although the stomach being full could account for satiety, it would have to be full of food containing the proper nutrients which would then stimulate the receptors in the stomach lining sensitive to the nutrients disolved in the digestive juices.
Common sense suggests that feeding stops when the stomach is full.
This is true enough, but it is only part of the story, for animals will stop eating even when their stomach is partially full. This will only happen, however, if they have ingested a nutritious substance. If the stomach is filled with an equal volume of nonnutritive bulk, the animal will continue to eat. This suggests that the stomach walls contain receptors that are sensitive to the nutrients disolved in the digestive juices. They signal the brain that nutrient supplies to the internal environment are on their way as food is about to enter the intestines.