“The interaction of marijuana with brain development could be a significant problem.” Dr Han Breiter, Professor of Psychiatry and co-study author
A team of researchers has warned that even casual marijuana use can damage the brain.
Previous studies have shown that significant marijuana usage by teens can have a profound impact on the person’s brain even leading to serious mental illnesses such as schizophrenia.
Now researchers from Northwestern University Feinberg School of Medicine and Harvard University have found even casual marijuana usage by teens, as little as once a week, can affect their brain. The results of the study were published in the Journal of Neuroscience.
Doctor Hans Breiter is a professor of psychiatry and behavioral sciences at Northwestern University. As co-leader of the study, he believes no one under the age of 30 should use marijuana because of the potential damage to the brain.
“This study raises a strong challenge to the idea that casual marijuana use isn’t associated with bad consequences. Some people only used marijuana to get high once or twice a week.
People think a little recreational use shouldn’t cause a problem, if someone is doing OK with work or school. Our data directly says this is not the case.”
In an interview with FoxNews, Breiter said:
“There were abnormalities in their working memory, which is fundamental to everything you do.”
Their study challenges notions that marijuana is a “safe” drug put forward by many pushing for its legalization. On January 1, 2014, Colorado legalized the sale of marijuana in that state.
Brain scans reveal marijuana induced abnormalities
Using MRIs (magnetic resonance imaging), the team studied the brains of 40 people aged 18 to 25. Half the group used marijuana regularly from once a week to daily, the other half didn’t.
They scanned their brains in two area — the nucleus accumbens (NAC) and amygdala — measuring their shape, volume and density. The two areas, found in the lower part of the brain, affect emotions, motivation and decision-making.
NAC also controls other areas such as fear, aggression, impulsiveness, pleasure, laughter and addiction.
The result of the scans surprised the researchers. The scans showed that the brains of all who used marijuana were affected. The researchers said:
“For the NAC, all three measures [volume, density and shape] were abnormal in a dose-dependent way, meaning the changes were greater with the amount of marijuana used.”
In terms of the amygdala, they found abnormalities in density and shape. But only the volume showed increased change with higher marijuana use. Though the test group was small, it nevertheless sets off alarm bells about the growing trend to legalize the drug.
The research group believes their study confirmed a condition called “amotivational syndrome” associated with marijuana usage. This results in people losing a sense of purpose and focus in their life and have a reduced interest in achieving goals.
- Casual marijuana use linked with brain abnormalities, study finds: FoxNews
- Even casual use of cannabis alters brain, scientists warn: The Telegraph