Seven Surprising Insights on Cannabis and Brain Impact

WHO:

The Washington Post - Stephen Lankenau, director of Drexel University’s Medical Cannabis Research Center

Yahoo - Stephen Lankenau, director of Drexel University’s Medical Cannabis Research Center

WHAT:

The Washington Post - A federally commissioned paper published in the Journal of Studies on Alcohol and Drugs found that anything more than one drink a day increases mortality.

Yahoo - Cannabis use among younger adults is rising, with increasing numbers of patients arriving in emergency rooms with signs of cannabis intoxication.

Yahoo - Cases of cannabinoid hyperemesis syndrome quadrupled among adults ages 18 to 35 between 2016 and 2022.

Yahoo - In 2002, about 25 million Americans reported using cannabis in the past year; by 2023, that number had climbed to nearly 70 million.

Yahoo - Daily or near-daily cannabis use has increased faster than occasional use, with adults over 35 being among the fastest-growing groups of users.

Yahoo - A 2024 study published in JAMA Network Open found no major association between moderate cannabis use and cognitive decline in middle-aged and older adults.

Yahoo - A 2025 study published in JAMA Network Open analyzed brain scans from over 1,000 young adults ages 22 to 36, finding that heavy lifetime users showed reduced brain activity during working memory tasks.

WHERE:

Yahoo - Recreational cannabis is now legal in 24 states and D.C.

WHEN:

Yahoo - A study published in February followed roughly 460,000 adolescents ages 13 to 17 into young adulthood.

Yahoo - A 2025 study of young adults with cannabis use disorder was published in JAMA Psychiatry.

Yahoo - A 2024 study from the Salk Institute focused on the cannabinoid cannabinol (CBN).

WHY:

Yahoo - Researchers are trying to understand what problematic cannabis use looks like and whether new habits and cultural norms could help prevent it.

Yahoo - The increasing potency of cannabis products may produce larger dopamine surges and more profound disruptions in perception.

HOW:

Yahoo - Researchers analyzed brain scans and cognitive performance to assess the effects of cannabis use on brain function.

(UPDATED June 19, 2026 01:57 UTC)

A new federally commissioned paper published in the Journal of Studies on Alcohol and Drugs reveals that consuming more than one drink a day can increase mortality rates. Meanwhile, cannabis use among younger adults is on the rise, with emergency rooms seeing a surge in patients showing signs of cannabis intoxication, and cases of cannabinoid hyperemesis syndrome have quadrupled among adults ages 18 to 35 from 2016 to 2022. As recreational cannabis becomes legal in 24 states and D.C., researchers are examining the effects of cannabis on brain function, analyzing brain scans and cognitive performance to better understand problematic use and its implications.