The effects of early handling on the partial reinforcement extinction effect and the partial punishment effect in male and female rats

• Published in: The Quarterly journal of experimental psychology. B, Comparative and physiological psychology Comparative and physiological psychology, 1987-08, Vol.39 (3), p.245-263
• Main Authors: Weiner, I., Halevy, G., Alroy, G., Feldon, J.
• Format: Article
• Language: English
• Subjects: Animal; Biological and medical sciences; Conditioning; Fundamental and applied biological sciences. Psychology; Learning. Memory; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology
• ISSN: 0272-4995; 1464-1321
• DOI: 10.1080/14640748708402267

Handled (Day 1-22) and non-handled infantile Wistar rats were tested in maturity for the partial reinforcement extinction effect (PREE) and the partial punishment effect (PPE). In Experiments 1 and 2, mature male and female rats were trained to run in an alley for food reward on a 1-trial/day schedule. In the PREE paradigm (Experiment 1), the partially reinforced group (PRF) received reinforcement on a quasi-random 50% schedule, while the continuously reinforced group (CRF) received reinforcement on every trial. In the test stage, both groups were given extinction training. In the PPE paradigm (Experiment 2), the partially punished (PP) group received, together with continuous reinforcement, shocks on a quasirandom 50% schedule, while the continuously reinforced group was reinforced on every trial. In test, all animals were given both reinforcement and shock on every trial. In Experiment 1, PREE-i.e. increased resistance to extinction in the PRF as compared to the CRF group-was more pronounced in the handled animals. More specifically, no PREE was obtained in the non-handled males, and in the non-handled females the PREE was reduced compared to the handled females. The results of Experiment 2 revealed no effect of handling or sex on PPE, that is, increased resistance to punishment in the PP group as compared to the CRF group was evident in all four conditions. In Experiment 3, handled and non-handled male rats were tested for the PREE using a multi-trial procedure in an operant chamber. PREE was obtained in the handled but not in the non-handled animals. The implications of these results for the differential effects of handling on male and female rats and the distinction between the PREE and PPE paradigms are discussed.