DRL INTERRESPONSE-TIME DISTRIBUTIONS - QUANTIFICATION BY PEAK DEVIATION ANALYSIS

Peak deviation analysis is a quantitative technique for characterizing interresponse-time distributions that result from training on differe ntial-reinforcement-of-low-rate schedules of reinforcement. It compare s each rat's obtained interresponse-time distribution to the correspon ding negative exponential distribution that would have occurred if the rat had emitted the same number of responses randomly in time, at the same rate. The comparison of the obtained distributions with correspo nding negative exponential distributions provides the basis for comput ing three standardized metrics (burst ratio, peak location, and peak a rea) that quantitatively characterize the profile of the obtained inte rresponse-time distributions. In Experiment 1 peak deviation analysis quantitatively described the difference between the interresponse-time distributions of rats trained on variable-interval 300-s and differen tial-reinforcement-of-low-rate 72-s schedules of reinforcement. In Exp eriment 2 peak deviation analysis differentiated between the effects o f the psychomotor stimulant d-amphetamine, the anxiolytic compound chl ordiazepoxide, and the antidepressant desipramine. The results suggest that peak deviation analysis of interresponse-time distributions may provide a useful behavioral assay system for characterizing the effect s of drugs.