Drug addiction is a multifaceted neuropsychiatric disorder characterized by the compulsive seeking and taking of a drug, despite the high likelihood of negative consequences. Addiction is notable for the complex, and still only partially understood, interactions between neurobiological, environmental, pharmacological, and genetic components. Multiple theories regarding the underlying mechanisms of addiction have been proposed (e.g., Goldstein and Volkow, 2002; Redish, 2004; Everitt and Robbins, 2005; Wise, 2008; Koob and Le Moal, 2008; Koob and Volkow, 2010), and although originally generated mostly from rodent studies, many, but not all, of these neurobiological mechanisms appear well conserved in non-human primates and, where studied, in humans. However, despite tremendous advances over the past several decades, translating preclinical findings of the molecular and cellular neuroadaptations following chronic drug intake has not as yet significantly improved clinical outcomes. As drug abuse is a uniquely human disease, it would seem that a better understanding of the profound disruption of motivational, affective and cognitive processes following, and/or predisposing individuals to drug use is critical to expedite treatment development.
