CBD and Brain Development
Cannabidiol (CBD), the non-intoxicating compound in cannabis and hemp, continues to draw attention as a potential treatment for disorders and illnesses ranging from epilepsy to cancer. Now a new brain imaging study suggests that a single dose of CBD can reduce symptoms of psychosis by “resetting” activity in three brain areas.
If replicable, the study offers the first evidence-based explanation for how CBD works in the brain to counteract psychosis, with results that could help generate new treatments.
Psychosis is not a single condition or disorder, but is rather a symptom of other disorders characterized by detachment from reality. Seeing, hearing or believing things that aren’t real, including hallucinations, is typical of a psychotic episode. While the exact causes of psychosis aren’t known, it’s thought to be triggered by mental illness, trauma, substance abuse and extreme stress. Even lack of sleep can spark an episode.
While psychosis is most often associated with schizophrenia, it actually affects a much larger segment of the population. At least 100,000 people a year experience their first onset of psychosis in the U.S., according to the National Institute of Mental Health.
This was a small study of 33 participants who were experiencing psychotic symptoms. A smaller group of healthy participants served as a control group. Half the psychosis group was given one 600 mg oral dose of CBD (a dose that was “previously effective in established psychosis” according to the study), the other half received an identical placebo capsule. The control group didn’t receive any drug. Then all of the participants completed a memory task designed to engage three brain areas that have been linked to the onset of psychosis (specifically the striatum, medial temporal cortex, and midbrain) while their brains were examined with an fMRI scanner.
The scans showed abnormal activity in the brains of the participants experiencing symptoms, as compared to the healthy control group – that much was expected. But the brains of those who had taken a dose of CBD showed less severe abnormalities than the brains of those who had taken a placebo, suggesting that the compound was “resetting” abnormal activity in the key brain areas.
“The results have started unravelling the brain mechanisms of a new drug that works in a completely different way to traditional anti-psychotics,” said the study’s lead author Dr. Sagnik Bhattacharyya from the Institute of Psychiatry, Psychology & Neuroscience at King’s College, London.
The study did have limitations. Aside from being a small study with a methodology unable to account for every factor that might influence the outcome, the researchers also noted that they can’t be sure the results weren’t caused by “the rapid changes in cerebral perfusion that are known to occur with a single dose of psychoactive drugs.” In other words, they may have witnessed a short-term effect that won’t last. Quoting from the study: “It is also unclear whether the effects of CBD will persist after longer-term dosing.”
The next step, already underway, is a large-scale human trial to replicate the results and determine if CBD is a viable treatment. If successful, the drug would be immediately differentiated from other meds on the market—including some that have been around since the 1950s—that produce inconsistent results. Some of the most common meds also have notoriously severe side effects, including muscle tremors and overpowering sedation.
“There is an urgent need for a safe treatment for young people at risk of psychosis,” added Dr. Bhattacharyya. “One of the main advantages of cannabidiol is that it is safe and seems to be very well tolerated, making it in some ways an ideal treatment.”
The study represents another move forward for CBD as a treatment for brain-based disorders. Earlier this year, the US FDA approved the first drug comprised of CBD to treat severe forms of epilepsy. While CBD derived from cannabis is a Schedule 1 controlled substance under federal law in the US, hemp-derived CBD is more widely accessible, though its legality in terms of federal law is still murky at best.
Members of this research team conducted an earlier study showing that CBD seems to counterbalance the effects of tetrahydrocannabinol (THC), the psychoactive compound in marijuana that gets users high. THC has been linked to the onset of psychosis in some users and appears to mimic aspects of psychosis in the brain. If CBD turns out to be an effective anti-psychotic, these findings will highlight yet another striking paradox of a plant that science is only now really beginning to understand.