New research into casual marijuana use during adolescence indicates that even limited usage can cause structural changes in the brain.
The study, published in The Journal of Neuroscience, examined the long-term impact of low and moderate usage of marijuana on the brain. Researchers specifically identified two regions of the brain that differ in size and shape between those who do not use marijuana and those who smoke once a week. The areas of the brain impacted are involved in emotion and motivation.
While many studies have focused on the long-term effects of heavy usage, the findings of this study indicate that low usage can cause substantial changes to the brain despite preconceptions that casual usage does not come with negative consequences. In examining the brains of participants, those who admitted to using marijuana more frequently had greater abnormalities in the affected areas of the brain compared to others.
Marijuana is the most commonly used illicit substance in the United States and rates of abuse increase as legislation is passed to legalize the drug. Nearly 18.9 million individuals in the United States report recent use in an analysis of the National Survey on Drug Use and Mental Health. Despite known side effects of impairments to memory, motivation and learning, marijuana continues to be largely misrepresented as a safe drug with no risk of negative consequences. The findings of this study disprove the incorrect belief that casual marijuana use is without consequence.
Aside from the physical effects marijuana has on body, its use has also been linked to increased risk of mental health disorders such as depression and anxiety. Drug use and co-occurring disorders often complicate one another and can worsen symptoms of both. In many cases, marijuana may be used as a means of self-medicating symptoms of depression and anxiety, but only serves to worsen it. The resulting effect is the creation of a cycle of abuse that is difficult to break.
Marijuana use may increase the likelihood of experimentation with other substances. While many believe marijuana use is not a gateway drug and safer than other illicit substances, recent research indicates that the side effects of abuse can be as detrimental as experimentation with other drugs.