Neuropsychological effects of cannabis use by continent and age: a systematic review
Frontiers in Psychology May 28, 2026 Lidia Venero-Hidalgo, Francisca Carvajal, Fernando Rodrı́guez de Fonseca et al.
Cannabis use during adolescence and young adulthood is linked to memory problems, especially in episodic and working memory, but effects on executive functions are less consistent and depend on age, how much cannabis is used, and the type of cognitive test. Studies from the Americas, many of which followed participants over time, more often found negative associations between cannabis use and cognitive performance. European studies showed mixed results, possibly due to differences in cannabis products, patterns of co-use, and measurement methods. Evidence from Asia was limited. Overall, cognitive differences are more reliably seen in adolescents than in young adults, shaped by developmental, methodological, and contextual factors.