USE OF CLASSICAL-CONDITIONING PROCEDURES IN BEHAVIORAL PHARMACOLOGY

While operant conditioning clearly dominates the field of behavioral pharmacology, over the past 10 years, classical conditioning has been used more frequently to study the effect of drugs on behavior. In particular, the rabbit nictitating membrane response (NMR) has been used to study the effects of drugs on learning. This procedure offers a number of advantages over other assessments of learning in mammals to the study of drug effects on learning. First, because the rabbit NMR is well characterized behaviorally, it is possible to relate a drug effect to a particular behavioral process (e.g., to an effect directly on learning vs. an effect on the psychological processing of the unconditioned stimulus). In addition, with recent advances in determining the neuroanatomical basis of the conditioned NMR, it may also be possible to relate a drug effect on learning to an effect at a particular anatomical locus. Finally, because the conditioned response is acquired rapidly, the effect of a drug on learning can be assessed rapidly within a large group of animals. The current paper details the behavioral techniques which have been developed to study the effects of drugs, in particular the opioids, on classical conditioning. A number of studies which have used classical conditioning procedures in the rabbit to study drug effects on acquisition, maintenance, and differentiation of conditioned responses are reviewed. Copyright © 1990 Wiley‐Liss, Inc.