Cannabidiol (CBD), the non-intoxicating compound in marijuana, continues drawing 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.