Effects of Cannabis on Impulsivity: A Systematic Review of Neuroimaging Findings
Current Pharmaceutical Design May 10, 2014 Johannes Wrege, André Schmidt, Anna Walter et al. 96 citations
A systematic review of 17 studies (13 meeting inclusion criteria) examined cannabis's effects on impulsivity, disinhibition, and motor control, with a focus on neuroimaging findings from acute and chronic use up to May 2012. Functional imaging studies indicate that chronic cannabis users have lower prefrontal blood flow than controls, while acute administration of THC or marijuana increases brain metabolism in several regions during impulsivity tasks. Structural imaging studies found reduced prefrontal volumes and white matter integrity in cannabis users, which may mediate abnormal impulsivity and mood. The review concludes that more longitudinal studies are needed to determine whether impulsivity precedes cannabis use or cannabis aggravates impulsivity and discontinuation.