DSM-5 from the viewpoint of basic study of dependence and addiction

In this review, current progress of neurobehavioral research using animal model of dependence and/or addiction is described in light of DSM-5. Although the terms "dependence" and "abuse" are deleted in DSM-5, the concept of dependence and the related animal experiments, drug self-administration, conditioned place preference, and drug discrimination are still useful to predict abuse liability of chemical substances. At the same time, it is necessary to model addictive nature of behavior in animals. Impulsivity, compulsivity, and comorbidity of addiction to other mental disorders are the major topics of such research area. At the same time, basic research aimed at treatment of dependence/addiction has been progressed. For example, a methamphetamine monoclonal antibody, a new chemical acting on DARPP-32 (dopamine and c-AMP-regulated phophoprotein-32), a galanin analogue, oxytocin, and others are included in such attempt. As DSM-5 mentioned the brain reward system as the major site of substance-related and addictive disorders, clinicians would be more interested in biological substrates of dependence/addiction. It is expected that the emergence of new diagnostic criteria promotes mutual communication between basic and clinical researchers.