Damage Nerve Fibers in Key Brain Structure
A first-of-its-kind study of the effects of high-potency marijuana on brain structure shows it can damage the corpus callosum (imaged above), a huge section of white matter that consists of nerve fibers responsible for communicating between the two halves of the brain. This part of the brain is rich in receptors to which THC binds.
Study results “reflect a sliding scale where the more cannabis you smoke and the higher the potency, the worse the damage will be,” says Dr. Paoloa Dazzan, reader in neurobiology of psychosis at the institute of psychiatry, psychology, and neuroscience at King’s College London and senior researcher of the study.
Scientists recruited 56 people reporting a first-episode psychosis and 43 people without psychosis and administered clinical and brain imaging assessments to all. The structure of the white matter of high-potency marijuana users in both groups – those with and those without psychosis – was significantly damaged.
High-potency marijuana they used contained from 16-22% THC and 0.1% CBD. The Brits call this “high-potency” and “skunk,” while U.S. marijuana dispensaries and pot shops in legal states call this average. Here, marijuana concentrates such as wax or shatter contain much higher levels of THC, from 50-75%.
The researchers note that their study cannot confirm that THC caused the structural changes – it may be that people with damaged white matter are more likely to smoke marijuana. But what they can say is that if you smoke marijuana frequently and it is high-potency, your brain is different from the brains of those who use low-potency marijuana infrequently or not at all.
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NFIA consists of families, scientists, business leaders, physicians, addiction specialists, policymakers, and others committed to protecting children from addictive drugs. Our vision is:
- Healthy, drug-free kids
- Nurturing, addiction-free families
- Scientifically accurate information and education
- A nation free of Big Marijuana
- Smart, safe, FDA-approved medicines developed from the cannabis plant (and other plants)
- Expanded access to medicines in FDA clinical trials for children with epilepsy
About SAM (Smart Approaches to Marijuana)
SAM is a nonpartisan alliance of lawmakers, scientists and other concerned citizens who want to move beyond simplistic discussions of “incarceration versus legalization” when discussing marijuana use and instead focus on practical changes in marijuana policy that neither demonizes users nor legalizes the drug. SAM supports a treatment, health-first marijuana policy.
SAM has four main goals:
- To inform public policy with the science of today’s marijuana.
- To reduce the unintended consequences of current marijuana policies, such as lifelong stigma due to arrest.
- To prevent the establishment of “Big Marijuana” – and a 21st-Century tobacco industry that would market marijuana to children.
- To promote research of marijuana’s medical properties and produce, non-smoked, non-psychoactive pharmacy-attainable medications.