Type of event:
Presenter: Professor Murat Yucel
Institution: University of Melbourne
Cannabis is arguably the most hotly debated drug of abuse. Its profound effects on the mind have been known for at least 5000 years and have polarised attitudes, with long-‐standing controversies surrounding the ‘recreational’ use of cannabis, its legalisation, and its therapeutic potential, as well as harm.
Prof Yücel will present data showing that long term and heavy cannabis use Is associated with significantly reduced brain volumes and white matter integrity in medial temporal and cerebellar regions, as well as, having memory impairment and being more likely to develop sub-‐threshold psychotic symptoms. Importantly, the associations between cannabis exposure, loss of brain volume/integrity, and severity of psychotic-‐like experiences are dose-‐dependent, suggesting that they are intricately linked.
He will also present the results of two recent studies -‐ a meta-‐analysis and an empirical study, which examined the effects of cannabis use on cognitive functioning in psychotic patients. The findings showed that psychotic patients with an early onset and heavy use of cannabis are associated with superior cognitive functioning compared to psychotic patients without a significant cannabis use history. These findings are interpreted to suggest that heavy cannabis use during early adolescence can be a component cause psychotic disorders in some individuals, despite the fact that cognitive deficits associated with a neurodevelopmental vulnerability are not observed in this same group.
Our recent findings raise questions regarding the use of drugs during adolescence and have important implications for our understanding of the relationship between drug use, brain development and mental health, as well as prevention and early intervention approaches.