Addiction, the most severe form of substance use disorder, is a chronic brain disorder molded by strong biosocial factors that has devastating consequences to individuals and to society. Our understanding of substance use disorder has advanced significantly over the last 3 decades in part due to major progress in genetics and neuroscience research and to the development of new technologies, including tools to interrogate molecular changes in specific neuronal populations in animal models of substance use disorder, as well as brain imaging devices to assess brain function and neurochemistry in humans. These advances have illuminated the neurobiological processes through which biological and sociocultural factors contribute to resilience against or vulnerability for drug use and addiction. The delineation of the neurocircuitry disrupted in addiction, which includes circuits that mediate reward and motivation, executive control, and emotional processing, has given us an understanding of the aberrant behaviors displayed by addicted individuals and has provided new targets for treatment. Most prominent are the disruptions of an individual’s ability to prioritize behaviors that result in long-term benefit over those that provide short-term rewards and the increasing difficulty exerting control over these behaviors even when associated with catastrophic consequences. These advances in our understanding of brain development and of the role of genes and environment on brain structure and function have built a foundation on which to develop more effective tools to prevent and treat substance use disorder.
Nora D. Volkow, M.D., Maureen Boyle, Ph.D.
The American Journal of Psychiatry, April 25, 2018