02/05/2025
A recent study published in JAMA has provided significant insights into the effects of heavy cannabis use on brain function, particularly concerning working memory. Conducted by researchers from the University of Colorado Anschutz Medical Campus, this study is considered the largest of its kind, involving over 1,000 young adults aged 22 to 36. Heavy use was defined as having used cannabis over 1000 times in a lifetime. (Ex. 2 - 3 times a day for a year would be ~700 - 1000 times)
Findings revealed that 63% of individuals identified as heavy lifetime cannabis users exhibited reduced brain activity during tasks involving working memory. Similarly, 68% of recent cannabis users demonstrated comparable reductions in brain activity. These decreases were observed in critical brain regions associated with decision-making, memory, and emotional processing, such as the prefrontal cortex and anterior insula.
Dr. Joshua Gowin, the lead author of the study, emphasized the importance of understanding both the benefits and potential risks associated with cannabis use. He noted that while the study found significant effects on working memory, other cognitive functions appeared unaffected. Dr. Gowin also suggested that abstaining from cannabis before engaging in tasks that require cognitive effort could enhance performance.
The researchers acknowledged that the cross-sectional nature of the study limits the ability to establish causation. They recommend further longitudinal research to explore the long-term impacts of cannabis use on brain function and to determine whether these effects are reversible with sustained abstinence.
This study contributes to the growing body of literature examining the cognitive effects of cannabis, highlighting the need for informed decision-making regarding its use, especially among young adults.
