Research using brain scans has concluded that reduced dopamine release in the brains of persons with severe marijuana dependence resembles a mechanism commonly seen in other behavioral health disorders.
The study, published online this week in Molecular Psychiatry, involved 11 individuals with cannabis use disorder and 12 healthy controls. The marijuana-dependent individuals had significantly lower dopamine release in the striatum, a region that has a role in working memory, impulsivity and attention. Because the marijuana-dependent subjects had no other comorbid conditions, the changes in dopamine release could not be attributed to other behavioral illnesses.
The lower dopamine release was associated with greater emotional withdrawal and inattention in the group with cannabis use disorder, researchers reported. The study was co-authored by Nora D. Volkow, MD, director of the National Institute on Drug Abuse (NIDA).