Rewiring the Addicted Brain: Circuits-Based Treatment for Addiction

摘要

Drug addiction is a chronic relapsing brain disorder, characterized by compulsion to seek and take the drug, loss of control in limiting the intake despite harmful consequences, and negative emotional state when access to the drug is prevented (American Psychiatric Association 2013). The term addictions is now encompassed by the term substance use disorders (SUDs), since the DSM-5 consider substance abuse and substance dependence as one diagnostic construct in which the severity of SUDs ranges from mild to moderate depending on how many criteria apply (American Psychiatric Association 2013). Compelling evidence has shown that the initial exposure to substance abuse exerts a reinforcing effect by activating reward circuits in the brain mainly encoding for a voluntary behavior, whereas the repeated drug administration progressively impairs brain functions by altering the ability to self-control over drug-seeking and -taking behaviors (Volkow et al. 2016). Classically, an SUD is conceptualized as a complex three-stage recurring cycle, worsening over time and involving neuroplastic changes in three major circuits: (i) reward-basal ganglia system in the binge/ intoxication stage; (ii) extended amygdala and stress response system dysfunctions related to the withdrawal negative affect stage; and (iii) prefrontal cortex (PFC) and executive function systems related to the preoccupation/ anticipation stage (Goldstein and Volkow 2002; George and Koob 2010). Progress in understanding the neurobiol-ogy of addiction has been made through the study of either animal models or brain-imaging studies in addicted indi-