chronic, neurobiological disease, with genetic, psychosocial, and environmental factors influencing its development and manifestations. It is characterized by behaviors that include impaired control over drug use, compulsive use, continued use despite harm, and craving (Ries et al. 2009; Volkow et al. 2011). Substance Dependence, a Psychiatric diagnosis is defined as “repeated use of alcohol or other drugs despite problems related to use of the substance (O'Brien 2008). Critical to these medical diagnoses of severe addiction is the continued use of drugs despite the harm to the individual, family and community due to the loss of ability to alter behavior in spite of problems. This review will describe changes in the neurobiology of the brain related to severe addiction.
