MedicalResearch.com Interview with:
Professor, Rita Z. Goldstein, PhD
Department of Psychiatry (primary)
and Department of Neuroscience, Friedman Brain Institute (secondary)
Chief, Neuropsychoimaging of Addiction and Related Conditions (NARC) Research Program
Anna Zilverstand PhD
Assistant Professor, Psychiatry
Icahn School of Medicine at Mount Sinai
The Leon and Norma Hess Center for Science and Medicine
New York, NY 10029
MedicalResearch.com: What is the background for this study? What are the main findings?
Response: In comparison to previous reviews that often focused on investigating select brain circuits, such as the reward network, our review is the first to systematically discuss all brain networks implicated in human drug addiction. Based on more than 100 neuroimaging studies published since 2010, we found that six major brain networks showed altered brain function in individuals with addiction. These brain circuits are involved in a person’s ability to select their actions (executive network), in directing someone’s attention (salience network), in adaptive learning of new behaviors (memory network), in the automatization of behaviors (habit network), in self-reflection (self-directed network) and the valuation of different options (reward network).
When individuals with addiction are confronted with pictures of drug taking, all of these networks become very highly engaged; however, when the same individuals are confronted with scenes depicting other people, their brains show a reduced reaction as compared to healthy individuals, indicating less involvement. Similarly, the brain of an addicted individual is less engaged when making decisions (that are not relevant to their drug taking) or when trying to inhibit impulsive actions. We further found that some impairments of brain functions, such as alterations underlying the difficulty to inhibit impulsive actions, seem to precede drug addiction, as we observe similar impairments in adolescents that later go on to abuse drugs. However, particularly the impairments in the executive network (involved in the ability to inhibit impulsive actions), the valuation network (which computes the value of an option) and the salience network (that directs attention towards events) seem to be getting worse with more severe drug use and also predict if someone is likely to relapse or not.
The good news is that we also found that it is possible to (partially) recover and normalize brain function in these networks through treatment. Importantly, the widespread alterations of brain function were independent of what drug an individual was addicted to (marijuana, alcohol, cigarettes, cocaine, methamphetamine, heroin, amongst others).
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