versão impressa ISSN 1657-9267
APARICIO, CARLOS F.. Effects of Haloperidol on Responding Maintained with Food and Sucrose-Water. Univ. Psychol. [online]. 2010, vol.9, n.3, pp. 641-663. ISSN 1657-9267.
The "hedonic" value of reinforcers is mediated by dopamine. Accordingly, haloperidol diminishes the value of reinforcers, by interfering with the emission of operant behaviors. Alternatively, the interference of dopamine transmission does not prevent animals from eating food. Thus, reinforcers remain intact after the administration of haloperidol. We assessed these possibilities with eight Wistar rats and two types of reinforcers, food-pellets and sucrose-water, delivered under multiple reinforcement schedules. In general, lever presses maintained by food-pellets were higher than those maintained by sucrose-water. Haloperidol produced dose -related decreases in lever presses and obtained reinforcers. Different doses had no effect on the number of lever presses. Subcutaneous administrations of haloperidol produced higher decreases in lever presses than intra-peritoneal administrations. Decreases in lever pressing were not necessarily accompanied by substantial reductions in obtained food-pellets and sucrose-water reinforcers; under the effects of haloperidol rats continued to produce a considerable number of both types of reinforcers.
Palavras-chave : Haloperidol; Anhedonia; Multiple Schedules; Food-Pellets; Sucrose-Water; Rats; Operant Behavior; Causality; Haloperidol; ratas.