EFFECTS OF LOW-DOSES OF NEUROLEPTICS ON TEMPORAL REGULATION IN A DIFFERENTIAL REINFORCEMENT OF RESPONSE DURATION (DRRD) SCHEDULE IN THE DOG

It has been shown that low doses of neuroleptics could disinhibit behaviour in animals as well as in man. This study aims to measure the effects of low doses of haloperidol (0.01, 0.05, 0.1 mg/kg) and sulpiride (5, 10, 15 mg/kg) in the dog using a differential reinforcement of response duration (DRRD) schedule with positive and negative external stimuli. Together with a decrease in response rate, a leftward shift in the temporal distribution of response duration is measured. These results are discussed in terms of a deregulation of the internal clock, a lessening in the ability to wait for the reward, a reduction in the frustration of not obtaining reinforcements when errors are made and an increase in the sensibility to reinforcement through appetite stimulation or decrease in the satiety level.