Sham feeding experience produces a conditioned increase of meal size

The effect on intake of reversing the flavors and locations that had been associated with sham feeding and real feeding was measured in two experiments. Rats were equipped with chronic gastric cannulas to permit sham feeding. Flavors and locations were associated with a real meal of milk or with sham feeding the same volume of flavored milk or with sham feeding about six times as much milk. In both experiments, the flavors and locations with sham feeding produced a conditioned increase in meal size during real feeding. This conditioned increase in meal size appeared to be primarily due to a conditioned decrease in the satiating potency of the milk because it was dissociated from a conditioned increase in preference measured in a four-minute choice test.