Cannabis effects on brain structure, function, and cognition: considerations for medical uses of cannabis and its derivatives

Am J Drug Alcohol Abuse. 2019;45(6):563-579. doi: 10.1080/00952990.2019.1634086. Epub 2019 Jul 31.


Background: Cannabis is the most widely used illicit substance worldwide, and legalization for recreational and medical purposes has substantially increased its availability and use in the United States.Objectives: Decades of research have suggested that recreational cannabis use confers risk for cognitive impairment across various domains, and structural and functional differences in the brain have been linked to early and heavy cannabis use.Methods: With substantial evidence for the role of the endocannabinoid system in neural development and understanding that brain development continues into early adulthood, the rising use of cannabis in adolescents and young adults raises major concerns. Yet some formulations of cannabinoid compounds are FDA-approved for medical uses, including applications in children.Results: Potential effects on the trajectory of brain morphology and cognition, therefore, should be considered. The goal of this review is to update and consolidate relevant findings in order to inform attitudes and public policy regarding the recreational and medical use of cannabis and cannabinoid compounds.Conclusions: The findings point to considerations for age limits and guidelines for use.

Keywords: Cannabis; brain; cannabidiol; cognition; endocannabinoid; medical marijuana; morphology; tetrahydrocannabinol.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Age Factors
  • Attention Deficit Disorder with Hyperactivity / drug therapy
  • Autism Spectrum Disorder / drug therapy
  • Brain / drug effects*
  • Brain / pathology
  • Cannabidiol / pharmacology*
  • Cannabidiol / therapeutic use
  • Cognition / drug effects*
  • Dronabinol / pharmacology*
  • Endocannabinoids / metabolism
  • Epilepsies, Myoclonic / drug therapy
  • Humans
  • Infant
  • Lennox Gastaut Syndrome / drug therapy
  • Medical Marijuana / therapeutic use*
  • Organ Size
  • Spasms, Infantile / drug therapy


  • Endocannabinoids
  • Medical Marijuana
  • Cannabidiol
  • Dronabinol

Supplementary concepts

  • Epileptic encephalopathy, Lennox-Gastaut type