Figure 4.
Schematic diagram of a reinforcer devaluation task. In the training phase, the subject learns to associate pairs of cues with one of two food reward (e.g., peanuts and raisins) or non-reinforcement. Typically a large set of cue pairs is used, although only two are shown here. After training, and before testing, the subject is offered free access to one of the rewards (e.g., peanuts) until satiation (the subject voluntarily stops consumption of the reward). The monkey’s reward preferences are assessed both before initial training, and after satiation. In the test phase, the subject is offered a choice between cues that are associated with the devalued food (in this case, peanuts) or the non-devalued food (raisins). Normal monkeys will preferentially choose the cue associated with the non-devalued food. Monkeys lacking amygdala function continue to choose the cue associated with the devalued food; see [56] for more details.