0
0
A groundbreaking study by McGill University has revealed that cannabis use exacerbates brain changes in young adults at high risk of psychosis, offering fresh insight into the condition and raising the potential for new, more effective treatments.
The research, published in JAMA Psychiatry, identifies a marked decrease in synaptic density—the connections between neurons that facilitate brain communication—among individuals at risk of psychosis. This change in brain structure was found to be more pronounced in those who used cannabis, suggesting that the drug may hinder the brain’s natural development process.
Dr. Romina Mizrahi, senior author of the study and a professor in McGill’s Department of Psychiatry, explained that the findings highlight how cannabis use disrupts the brain’s ability to refine and “prune” synapses—an essential function for healthy brain development. “Not every cannabis user will develop psychosis, but for some, the risks are high. Our research helps clarify why,” Dr. Mizrahi said.
Study Details and Implications
The study, which involved 49 participants aged 16 to 30—including individuals showing early signs of psychosis and those considered at high risk—used advanced brain imaging technology to track structural changes in the brain. The results indicate that individuals with lower synaptic density are more likely to experience symptoms like social withdrawal and lack of motivation, which are often difficult to treat and affect personal and professional relationships.
Belen Blasco, the study’s first author and a PhD student in McGill’s Integrated Program in Neuroscience, emphasized that current treatments for psychosis largely focus on addressing hallucinations and other psychotic symptoms but do not effectively target social dysfunction or cognitive challenges. “By focusing on synaptic density, we may eventually develop therapies that enhance social function and quality of life for those affected,” Blasco explained.
Cannabis and Psychosis Risk
Cannabis use has long been identified as a risk factor for developing psychosis, which can progress to conditions like schizophrenia. However, this study is the first to measure the brain’s structural changes in real time among a high-risk group. The findings underscore the potential impact of cannabis on young adults’ brain development, particularly in those already predisposed to mental health disorders.
The researchers now plan to investigate whether these brain changes could serve as early indicators for the development of psychosis, potentially enabling earlier intervention and better-targeted treatments.
Future Research
The next phase of the study will explore whether the observed brain changes can predict the onset of psychosis, potentially offering a critical window for preventative care. This research was conducted at the Douglas Mental Health University Institute and McGill University’s Montreal Neurological Institute-Hospital, with support from the Canadian Institute of Health Research.
As the study opens new avenues for understanding the relationship between cannabis use and psychosis, it brings hope for more effective treatments, particularly for those who struggle with the social and motivational aspects of the disorder, which have long been difficult to address.
Source: McGill University
Journal Reference: Blasco, M. B., et al. (2024). Synaptic Density in Early Stages of Psychosis and Clinical High Risk. JAMA Psychiatry. doi.org/10.1001/jamapsychiatry.2024.3608
