The most important unresolved issue in the addictions: conceptual chaos.

This article suggests that the field of addiction study and treatment remains in a state of conceptual chaos. The addictions is an emerging scientific field that lacks conceptual clarity. To develop the precision necessary for scientific advance, we must begin by developing improved definitions of substance use, abuse, dependence, and addiction. Complicating matters, psychoactive substance use is not a necessary and sufficient cause of addiction. For example, pathological gamblers experience addiction, including tolerance and withdrawal, often in the absence of any drug use. The neurobiology of subjective experience may be a more important factor in helping to explain addictive behaviors. Consequently, this article concludes that it is improper to consider drugs as the necessary precondition for addiction. Better operational definitions will advance addictions research.