Especially among teens, there is perception that, in comparison to ‘dangerous’ legal drugs like alcohol and tobacco, marijuana is relatively safe.
Surveys suggest that one-third of high school seniors have tried pot in the last year and less than half of 17-year-olds believe the drug is harmful.
A new review of the evidence, however, to be published in Neuropharmacology, suggests the drug may have harmful consequences for the growing adolescent brain.
Hurd et al. (2013) reviewed data from more than 120 studies to examine the relationship between marijuana use and the teenage brain.
They find that marijuana may be harmful for a particular type of vulnerable adolescent, possibly leading to behavioural problems and addiction.
One of the study’s authors, Didier Jutras-Aswad explained:
“It is now clear from the scientific data that cannabis is not harmless to the adolescent brain, specifically those who are most vulnerable from a genetic or psychological standpoint. Identifying these vulnerable adolescents, including through genetic or psychological screening, may be critical for prevention and early intervention of addiction and psychiatric disorders related to cannabis use.”
While the research on the long-term effects of marijuana use, especially in vulnerable populations, is still relatively young, the warning signs are mounting:
- A study of 1,037 individuals followed from birth found that persistent cannabis use was associated with cognitive decline over the years. More worryingly these problems continued even after drug use ceased (Meier et al., 2012).
- A review of many studies on marijuana use has found that it can damage the encoding, storage, manipulation and retrieval mechanisms of memory (Solowij & Battisti, 2008).
Teenagers should be aware that, for those with particular vulnerabilities, like neuroticism and anxiety, marijuana is not as harmless as many assume.
About the author
Psychologist, Jeremy Dean, PhD is the founder and author of PsyBlog. He holds a doctorate in psychology from University College London and two other advanced degrees in psychology.
He has been writing about scientific research on PsyBlog since 2004. He is also the author of the book “Making Habits, Breaking Habits” (Da Capo, 2003) and several ebooks:
- Accept Yourself: How to feel a profound sense of warmth and self-compassion
- The Anxiety Plan: 42 Strategies For Worry, Phobias, OCD and Panic
- Spark: 17 Steps That Will Boost Your Motivation For Anything
- Activate: How To Find Joy Again By Changing What You Do
Image credit: miggslives
How Common Drugs Affect the Mind
→ This post is part of a series on how common drugs affect the mind:
- What Caffeine Really Does to Your Brain
- Teen Myth: Marijuana is a ‘Safe Drug’
- Which Cognitive Enhancers Really Work: Brain Training, Drugs, Vitamins, Meditation or Exercise?
- Psychedelic Drug Use Not Associated With Mental Health Problems
- The ‘Beer Goggles’ Effect: What Causes It?
- Marijuana Does Not Cause Schizophrenia
- Caffeine Improves Long-Term Memory When Consumed After Learning