Context conditional flavor preferences in the rat based on fructose and maltodextrin reinforcers

In three experiments, rats were exposed to a flavor preference procedure in which flavor A was paired with the reinforcer and flavor B presented alone in Context 1, while in Context 2 flavor A was presented alone and flavor B with the reinforcer. With fructose as the reinforcer both two- and one-bottle training procedures produced a context-dependent preference (Experiments 1 and 2). With maltodextrin as the reinforcer two-bottle training produced a context-dependent preference (Experiment 1). Following one-bottle training with maltodextrin reinforcement rats demonstrated a context-dependent preference when the conditioned stimulus (CS)- was presented with a dilute solution of the reinforcer during training (Experiment 3B) but not when the CS- was presented alone (Experiments 2 and 3A). The pattern of results with maltodextrin reinforcement suggests that there was competition between the cue flavors and the taste of the maltodextrin as predictors of the postingestive consequences of the maltodextrin reinforcer. The fact that rats were able to display context-dependent flavor preferences is consistent with the idea that learned flavor preferences rely on the sort of cue-consequence associations that underpin other forms of conditioning which produce accurate performance on biconditional tasks. The differences between fructose- and maltodextrin-based preferences are discussed in terms of configural and elemental learning processes.