Post-ingestive positive controls of ingestive behavior

Post-ingestive negative controls of ingestive behavior are well characteriz ed. Nutrients act in the gut to inhibit meal size by direct actions on feed ing and by conditioning a satiation response to orosensory (flavor) stimuli . Accumulating evidence indicates that there are also post-ingestive positi ve controls of ingestion that operate by conditioning flavor preference and increased acceptance. In several experiments rats trained to consume a fla vored solution paired with intragastric carbohydrate infusions significantl y increased their solution intake. Drinking bout size and number, and lick rates and burst size were also increased by carbohydrate infusions. Whether intake is stimulated or inhibited by post-ingestive nutrient actions depen ds upon several factors. including most notably nutrient concentration. Pos t-ingestive positive controls need to be incorporated into theoretical mode ls of ingestive behavior. (C) 2001 Academic Press.