*The following is excerpted from an online article posted on PsychCentral.
New research shows a clear link between early and regular cannabis use by youth and alterations in brain circuits that support aspects of executive functioning.
The study finds that the frequent and regular use of cannabis in youth alters the neural circuits by which the mind governs, regulates, and guides behaviors, impulses and decision-making based on goals.
The researchers found that these brain alterations were less intense in individuals who recently stopped using cannabis.
However, the alterations were greater and more persistent in individuals who started using cannabis earlier, while the brain is still developing.
The study was published in the Journal of the American Academy of Child and Adolescent Psychiatry.
“Most adults with problematic substance use now were most likely having problems with drugs and alcohol in adolescence, a developmental period during which the neural circuits underlying cognitive control processes continue to mature,” said lead author Marilyn Cyr, Ph.D., a postdoctoral scientist with Columbia University.
“As such, the adolescent brain may be particularly vulnerable to the effects of substance use, particularly cannabis — the most commonly used recreational drug by teenagers worldwide.”
The study’s findings are based on functional magnetic resonance imaging (fMRI) data acquired from 28 adolescents and young adults between the ages of 14 and 23 with significant cannabis use and 32 age and sex-matched people who don’t use cannabis.
Participants were scanned during their performance of a Simon Spatial Incompatibility Task, a cognitive control task that requires resolving cognitive conflict to respond accurately, the researchers reported.
Compared to the non-users, the adolescents and young adults with significant cannabis use showed reduced activation in the frontostriatal circuits that support cognitive control and conflict resolution, according to the study’s findings.
Cyr noted that substance use and relapse rates are associated with control processes. Because of this, she said, “interventions based on neural stimulation, such as transcranial magnetic stimulation (TMS), and behavioral interventions, such as cognitive training, that specifically target the brain circuits underlying these control processes may be helpful as adjunct intervention strategies to complement standard treatment programs for cannabis use disorder.”