Effect of taste aversion conditioning on barpressing: Incentive or response interference

Abstract

Although there appears to be little argument that the frequency of instrumental responding is reduced when the reinforcer is a conditioned aversive taste, what accounts for the decrease has not been clarified. The present work examined two possibilities for the decrease: response or incentive interference. Rats trained to barpress were tested with either a palatable (tap water) or conditioned aversive flavour (NaCl) as the reinforcer, delivery of which was either contingent or noncontingent on the barpress response. Both contingency and palatability were associated with more frequent responding. On a subsequent nonreinforced test, rats previously rewarded noncontingently with a palatable flavour emitted more barpresses than rats that had been non-contingently rewarded with a conditioned aversive flavour. The results are interpreted as unambiguous support for the incentive interference account.