Given the growing trend toward permissive societal attitudes and the legalization of cannabis, coupled with an increasing recognition of its therapeutic potential, there has been a notable rise in cannabis consumption among older adults. Cognitive aging, one of the most prevalent concerns in this demographic, intersects with cannabis use, which shares several neural correlates. However, the precise impact of cannabis on the aging brain and cognitive function remains poorly understood. In this study, we leveraged large-scale data from the UK Biobank, which includes over 25,000 participants, to conduct a comprehensive examination of the relationships between cannabis use, normative aging, and cognitive function. Our focus was on how these factors correlate with brain functional network connectivity (FNC), aiming to elucidate the interactive effects underlying brain neuroimaging patterns. Our findings reveal that cannabis usage and healthy aging are associated with overlapping brain network configurations, particularly within the FNC between subcortical and sensorimotor regions, as well as between subcortical and cerebellar areas, albeit with significantly reversed effects. Notably, cannabis users exhibited superior performance across multiple cognitive domains, and interestingly, the effects of cannabis and cognition are presented concurrently across a range of brain systems. In conclusion, our study offers valuable insights into the potential influence of cannabis on brain aging and cognitive performance. The results suggest that cannabis users display brain network characteristics typically associated with younger brains, along with enhanced cognitive abilities, highlighting a potential modulatory role for cannabinoids and endocannabinoids in neurodegenerative processes, as explained through neural dedifferentiation and compensation theories.
Fu et al. (Fri,) studied this question.