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Cannabis Abstinence Improves Memory in Young People in First Month

In This Article

  • Stopping cannabis use can have a measurable effect on memory in adolescents and young adults
  • Effects on memory were observed within the first 30 days of abstinence from cannabis for the first time
  • The study is one of the first of its kind to prospectively detect and track changes in cognitive function over time associated with cannabis use

A team of researchers from the Center for Addiction Medicine (CAM) at Massachusetts General Hospital led by Randi Schuster, PhD, director of neuropsychology, and A. Eden Evins, MD, MPH, director of CAM, has found that halting cannabis use can have a measurable effect on memory in adolescents and young adults. The study, published in the Journal of Clinical Psychiatry, demonstrated that participants who were regular cannabis users showed improvements in memory functions that are essential for learning.

The team enrolled 88 participants ages 16 to 25 who acknowledged using cannabis at least once a week. One group of participants agreed to stop use for 30 days and all participants were given incentive payments for study visits and for maintaining abstinence. During the course of the study, the participants completed regular assessments of thinking and memory, and urine tests to verify the presence or absence of cannabis use.

The study is one of the first to prospectively track changes over time in cognitive function associated with stopping cannabis use. It is also the first to determine not just that cognitive improvement occurs with cannabis abstinence, but also that this improvement is detectable.

These results are notable at a time when recent surveys have shown that 13% of middle and high school students report cannabis use and the rates of daily use are increasing throughout high school. However, adolescence is a critical time for brain maturation, especially in the regions of the brain most susceptible to cannabis.

According to Dr. Schuster, these results strongly suggest that abstaining from cannabis helps young people learn and that continuing use might actually interfere with learning.

The CAM team is continuing this research with a larger follow-up study that includes younger participants and young nonusers for comparison.

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