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An important aspect of motivated behavior is that organisms will perform complex instrumental behaviors to gain access to stimuli such as food. In the present study, food-deprived rats were tested in an operant chamber in which the animals had a choice between pressing a lever to obtain a more-preferred food (Bioserve pellets), or free feeding on a less-preferred food (lab chow). Typically, rats pressed the lever to obtain the preferred food pellets, and ate little of the less-preferred food even though it was freely available. Pre-fed rats showed suppression of both lever pressing and feeding. Systemic administration of 0.1 mg/kg haloperidol (HP) led to a dramatic shift in the behavior of these rats, such that the number of lever presses was substantially reduced, but the amount of less-preferred food consumed showed a significant increase. This result occurred if the rats pressed a lever on either a CRF or FR5 …