Figure 5.

Schematic of contrast paradigm. A, Zero or 3% sucrose was delivered in the first portion of the behavioral session and 3 or 10% sucrose in the second part of the session. B, Bout lengths devoted to 3% sucrose consumption in an example session declined rapidly when the paired solution was switched from 0 to 10% sucrose (broken line). C, Mean bout length devoted to consumption of 3% sucrose declined significantly when paired with 10% sucrose, relative to pairing with 0% sucrose (p < 0.05 for all post hoc comparisons, one-way ANOVA; 19 behavioral sessions in 10 rats).