Medical Marijuana Effects On The Human Brain: Cannabis May Actually Improve Cognitive Function

By Kelsey Drain

A recent pilot study from Harvard University indicates that marijuana use actually improves cognitive performance, or our ability to use the knowledge and information we acquire, according to a news release. The research, though preliminary, provides a counterpoint to earlier reports which have linked weed to everything from reduced blood flow in the brain to an increased risk for Alzheimer's disease.

The news release reported that smoking weed, overall, improved brain function in a variety of ways: Patients answered self-reported questionnaires, which revealed that marijuana could moderately improve clinical state — including reduced sleep disturbance, decreased symptoms of depression, and positive changes in some aspects of quality of life.

To reach these conclusions, researchers examined 24 certified medical-marijuana patients over a three-month period. The team looked at participants’ cognitive proficiency by asking them to complete intelligence challenges, including the Stroop Color Word Test and Trail Making Test.
 
“After three months of medical marijuana treatment, patients actually performed better, in terms of their availability to perform certain cognitive tasks, specifically those mediated by the frontal cortex,” said lead researcher Staci Gruber, PhD, in the news release.

The brain’s prefrontal cortex is responsible for decision-making and complex behaviors, like planning, Medical Daily previously reported.

Researchers noted that the sample size is small and the initial findings are preliminary; however, the study is ongoing and will continue for the next two years.