Figure 1.

Task description. A, B, Animals were trained to perform a cued appetitive response task. A 1 s illumination of a centrally located, overhead cue light (conditioned stimulus) predicted the later availability of reward (6 ± 2 s after cue). Reward was available for 30 s, but rewards were typically consumed within the first 1–2 s of availability. Animals were given 30 cue–reward pairings in a session, with trials separated by 90 ± 30 s.