bioRxiv (Cold Spring Harbor Laboratory)
September 23, 2019
Kirsten C. S. Adam, Manoj K. Doss, Elisa Pabon et al.
2 citations
preprint
THC, the main psychoactive component in cannabis, impairs visual working memory—the ability to temporarily hold visual information in mind. Two double-blind, randomized crossover experiments with 23 healthy adults each found that oral THC (7.5 or 15 mg) reduced working memory performance, increased self-reported mind wandering, and decreased metacognitive accuracy about ongoing task performance. The authors also showed that short task durations and small sample sizes reduce the likelihood of detecting such drug effects.
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
October 1, 2020
Kirsten C S Adam, Manoj K Doss, Elisa Pabon et al.
THC, the main psychoactive component of cannabis, impairs visual working memory—the ability to temporarily hold information in mind. In two double-blind, randomized crossover experiments, healthy adults performed a visual working memory task after taking oral THC (7.5 or 15 mg) or a placebo. THC reduced working memory performance (effect size d = 0.65), increased self-reported mind wandering, and decreased the accuracy of participants' awareness of their own task performance. The findings suggest that THC disrupts working memory both by increasing mind wandering and by reducing metacognitive monitoring. The study also demonstrated that short task durations and small sample sizes can mask such drug effects.
Journal of psychopharmacology (Oxford, England)
September 1, 2019
Elisa Pabon, Harriet de Wit
Two double-blind, within-subjects studies tested whether a mobile phone app could detect cognitive impairment from oral doses of ∆9-tetrahydrocannabinol (0, 7.5, 15 mg). In 24 healthy non-daily cannabis users per study, tasks measuring cognitive speed, reaction time, fine motor ability, working memory, and time perception were completed during four-hour sessions at peak drug effect. ∆9-Tetrahydrocannabinol impaired performance on most standardized computer tasks but not on most brief phone tasks. The phone tasks' brevity likely reduced their sensitivity. The findings confirm impairment at two recreational doses but raise doubts about developing a phone-based field sobriety test for cannabis.