A recent study conducted at Yale University and the University of Oxford in the United Kingdom analysed cognitive performance among lifetime Cannabis sativa users, then compared them to non-users, in various aspects including memory, problem solving and intelligence.
In two large cohorts and using Mendelian randomisation, cannabis use was associated with slightly higher baseline cognitive scores but showed no link to longitudinal cognitive decline or dementia and no evidence of a causal effect was observed.
Researchers found that the participants with a history of cannabis use displayed much better cognitive performance. They noted in their study that use “was not associated with an increased risk of dementia”, and found “no supporting evidence of causal link with longitudinal cognitive decline later in life”.
“This study represents one of the largest observational investigations to date examining the relationship between cannabis use, cognitive function and dementia risk in older adults” researchers said. “Our findings are broadly consistent with prior population-based longitudinal studies that have not observed accelerated age-related cognitive decline associated with cannabis use” the researchers concluded.