Thirst measured by licking reinforced on interval schedules: Effects of prewatering and of bacterial endotoxin.

Abstract

In 2 experi-ments with groups of 5 231/2-hr. water-deprived rats, prefeeding different amounts of water reduced the rate of licking recorded by a drinkometer and reinforced with 0.11 ml of water on VI (variable interval) or FI (fixed interval) schedules, respectively. Statistically reliable linear relationships were secured on each individual rat. In Experiment 3, the effect of a bacterial endotoxin produced effects on the scheduled licking response similar to those previously observed on the volume of water consumed and on the rate of bar pressing. It is concluded that licking reinforced on a schedule is a good measure of thirst which has the advantage of not producing rapid satiation, and as a constant, effortless, and natural response may have other advantages.