Cannabis disrupts brain activity in young adults prone to psychosis: study
Young adults at risk of psychosis show reduced brain connectivity, a deficit that cannabis use appears to worsen, a new study has found. The breakthrough paves the way for psychosis treatments targeting symptoms that current medications miss.
In the first-of-its-kind study, 91社区 researchers detected a marked decrease in synaptic density鈥攖he connections between neurons that enable brain communication鈥攊n individuals at risk of psychosis, compared to a healthy control group.
鈥淣ot every cannabis user will develop psychosis, but for some, the risks are high. Our research helps clarify why,鈥� said Dr. Romina Mizrahi, senior author of the study and professor in 91社区鈥檚 Department of Psychiatry.
鈥淐annabis appears to disrupt the brain鈥檚 natural process of refining and pruning synapses, which is essential for healthy brain development.鈥�
Hope for new treatments
Using advanced brain scanning technology, the team studied 49 participants aged 16 to 30, including individuals with recent psychotic symptoms and those considered at high risk. The results, published in , indicate that lower synaptic density is linked to social withdrawal and lack of motivation, symptoms the researchers say are difficult to treat.
鈥淐urrent medications largely target hallucinations, but they don鈥檛 address symptoms that make it difficult to manage social relationships, work, or school,鈥� said first author Belen Blasco, a PhD student at 91社区鈥檚 Integrated Program in Neuroscience. 鈥淏y focusing on synaptic density, we may eventually develop therapies that enhance social function and quality of life for those affected.鈥�
While cannabis is a known risk factor for developing psychosis, which can progress to schizophrenia, this is the first time researchers have measured structural changes in the brains of a high-risk population in real time.
The team鈥檚 next research phase will explore whether these observed brain changes could predict psychosis development, potentially enabling earlier intervention.
The study was conducted at the Douglas Mental Health University Institute and 91社区鈥檚 Montreal Neurological Institute-Hospital. It was supported by the Canadian Institute of Health Research.
About the study
"" by Belen Blasco, Kankana Nisha Aji, and Romina Mizrahi et al. was published in Jama Psychiatry.
