Fig. 1

Pavlovian-Instrumental Transfer (PIT) Paradigm. Each participant learned the response-outcome associations between two key presses and two food outcomes, one hyperpalatable (O1), one non-hyperpalatable (O2), and the stimulus-outcome associations between five neutral graphical cues and five outcomes. Two cues were associated with the two food outcomes (O1, O2) trained to be linked to the two keys, i.e., specific food-predicting cues (S1, S2). Two cues were associated with the two food outcomes (O3, O4) not seen in instrumental training, i.e., general food-predicting cues (S3, S4). One cue was associated with a no-food outcome (O5) serving as the no-reward cue (S5). Non-cued and cued tests were conducted to evaluate response biases and response vigor in the presence of no cue, specific cues, general cues, and no-reward cues, following satiation on the hyperpalatable food consumed in instrumental training