The role of the stomach in eating.

The paper is concerned with the locus of provenance of satiety signals, what these are generated by, and pathways by which they reach the brain. Satiety signals are generated by the stomach and are of two kinds: distention at high volume and nutrient content. The former, but not the latter, are relayed to the brain via the vagus. Receptors that signal nutrient respond to digestive breakdown product of such nutrient. Further experiments are summarized to show that the gastric nutrient signals are calibrated through learning by association with various flavors. Previous to such learning, when food is novel, gastric controls do not operate, but regulation occurs through oropharyngeal metering.