The physiological mechanisms which subserve motivated behavior are almost entirely unknown. To attack this general problem, we have focused on the regulation of food intake as a representative motivated behavior. In particular, we have been investigating the unidentified factors, activated by food ingestion, which produce satiety in animals and humans.

Following our originial report in 1979 and on the basis of subsequent studies, we have proposed that endogenous mammalian bombesin-like peptides (found in the gastrointestinal tract and brain) play important roles in satiety. The goal is to understand the functions of these peptides in the peripheral generation and in the central neural processing of the physiological satiety signals which serve to limit meal size and to regulate the length of the intermeal interval.