Effects of punishment intensity on instrumental avoidance behavior.

Abstract

After bar-press avoidance training, 3 groups of marmosets were punished by different intensities of response-contingent shock for the avoidance response, while 3 groups were further avoidance trained without punishment. Avoidance shock was withdrawn during extinction, but punishment was retained for 3 punished groups, and introduced to 2 of the nonpunished groups. The extent to which punishment resulted in increased bar -press behavior with decreased avoidance efficiency was related to the punishment intensity. Furthermore, the treatment appeared to increase resistance to punished extinction. These results were interpreted in terms of competing requirements of earlier unpunished training and new demands of subsequent punished training, and establishment of response thresholds related to shock intensities.