Main Category: Alcohol / Addiction / Illegal Drugs
Also Included In: Neurology / Neuroscience
Article Date: 26 Jul 2013 - 8:00 PDT Current ratings for:
'Marijuana in adolescence can cause permanent brain damage'
New research may give backing to parents telling teens to "just say no." A study in mice from the University of Maryland School of Medicine reveals that regular use of marijuana during adolescence could damage brain function, potentially increasing the risk for schizophrenia and other psychiatric problems.
The study, which was recently published in Neuropsychopharmacology, had scientists examining cortical oscillations - patterns of the brain's neuron activity - in mice. These oscillations become abnormal when schizophrenia or other psychiatric disorders are present.
Researchers exposed young mice to low doses of tetrahydrocannabinol (THC), which is the active ingredient present in marijuana, for 20 days. Then the mice were returned to their family to continue developing.
When the mice became adults, the scientists discovered that their cortical oscillations were severely modified, and the mice showed signs of impaired cognitive functions.
Sylvina Mullins Raver from the University of Maryland says: "The striking finding is that, even though the mice were exposed to very low drug doses, and only for a brief period during adolescence, their brain abnormalities persisted into adulthood."
Interestingly, the researchers originally set out to test a hypothesis that marijuana use effects cortical oscillations in adults. But when they repeated the experiment on adult mice who had never been exposed to the drug previously, they found that both the oscillations and cognitive behavior stayed normal.
So, it appears that adolescence is the period of development when marijuana use can take its biggest toll. Senior author Dr. Asaf Keller adds:
"We looked at the different regions of the brain. The back of the brain develops first, and the frontal parts of the brain develop during adolescence.
We found that the frontal cortex is much more affected by the drugs during adolescence. This is the area of the brain that controls executive functions, such as planning and impulse control. It is also the area most affected in schizophrenia."
Now that marijuana has been legalized in 19 US states and the District of Columbia, the study's results about long-term effects of marijuana use are particularly relevant. The authors point to controversy spanning back to 20 years ago about whether or not marijuana use can cause permanent damage and contribute to psychiatric disorders.
Dr. Keller adds: "There is likely a genetic susceptibility, and then you add marijuana during adolescence and it becomes the trigger."
The research team will continue to study the changes in cortical oscillations with a view to potentially reverse the effects some day.
"We are hoping we will learn more about schizophrenia and other psychiatric disorders, which are complicated conditions," Dr. Keller says.
Written by Marie Ellis
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today Visit our alcohol / addiction / illegal drugs section for the latest news on this subject.
“Adolescent Cannabinoid Exposure Permanently Suppresses Cortical Oscillations in Adult Mice,” Sylvina M Raver, Sarah P Haughwout and Asaf Keller, Neuropsychopharmacology, doi:10.1038/npp.2013.164, published online 4 July 2013.
Please use one of the following formats to cite this article in your essay, paper or report:MLA
27 Jul. 2013.
Please note: If no author information is provided, the source is cited instead.
''Marijuana in adolescence can cause permanent brain damage''
Please note that we publish your name, but we do not publish your email address. It is only used to let you know when your message is published. We do not use it for any other purpose. Please see our privacy policy for more information.
If you write about specific medications or operations, please do not name health care professionals by name.
All opinions are moderated before being included (to stop spam). We reserve the right to amend opinions where we deem necessary.
Contact Our News Editors
For any corrections of factual information, or to contact the editors please use our feedback form.
Please send any medical news or health news press releases to:
Note: Any medical information published on this website is not intended as a substitute for informed medical advice and you should not take any action before consulting with a health care professional. For more information, please read our terms and conditions.
