The effects of naturalistic cannabis use on cognition and subjective experience in older adults with normal cognitive function
Journal of Psychopharmacology November 3, 2025 P. di Ciano, B. Le Foll, S. Zhao et al.
Older adults aged 65–78 who smoked their preferred legal cannabis with an average THC content of 18.7% showed decreased performance on the trail making test (versions A and B) 60 minutes after smoking, compared to when they were sober. However, the percentage of words retained in a verbal free recall test was significantly higher after cannabis, apparently due to a reversal in performance decrement. Smoked cannabis produced robust subjective drug effects. Correlations between blood THC levels and cognitive performance at 60 and 210 minutes were unclear. The findings suggest that older adults who use cannabis may show decrements on only some cognitive tests, along with marked changes in subjective experience.