This paper demonstrates that dopamine disruptions do not reduce thirst. Conditioned incentive properties of a food-paired conditioned stimulus remain intact during dopamine receptor blockade. The results indicate that while dopamine receptor blockade reduces overall levels of behavioral activity, it does not specifically attenuate the incentive properties of conditioned stimuli previously paired with reward. A methodology for separating neuroleptic effects on reinforcement and motor processes. This study introduces a methodology for asking whether dopamine antagonists disrupt reinforcement, without the motor confound that usually clouds such investigations.
Rats run down a straight-arm alley to receive food reward in a goal box.
After animals have acquired the running behavior, they undergo a series of extinction trials until running speeds have slowed again. Nondrugged animals will show a reinstatement of the running behavior after a single additional reinforcement trial. This response-reinstatement is blocked in animals under the influence of a dopamine antagonist drug during the reinforced trial. The results provide evidence for a dopamine involvement in food reinforcement. The methodology introduced in this paper has subsequently been employed to investigate dopamine involvement in the reinforcing properties of water, cocaine, amphetamine, and heroin.