Low-dose cannabis edibles impaired verbal memory but not other cognitive functions in regular users

At 150 minutes after consuming a cannabis edible averaging 7.3 mg THC, participants showed decreased performance on two verbal free recall measures. No effects were found on the useful field of view test or trail making test. Significant subjective intoxication was reported. Blood THC was not correlated with any cognitive outcomes.

Observational study where 22 participants consumed their own legally sourced cannabis edibles in the lab. Cognitive testing (verbal free recall, trail making, useful field of view) and subjective experience measures were administered at 150 and 270 minutes post-ingestion. Blood THC and metabolites were measured and correlated with cognitive outcomes.

Edible cannabis use is rising rapidly, yet almost all cognitive research has focused on smoked cannabis. This study provides rare data on how edibles at typical consumer doses affect thinking, finding a narrower cognitive impact than typically seen with smoking.

The finding that blood THC levels do not predict cognitive performance with edibles mirrors similar findings with smoked cannabis in older adults. This disconnect may reflect the complex pharmacokinetics of oral THC, including first-pass metabolism producing 11-OH-THC (which is more psychoactive), variable absorption rates, and individual differences in metabolism.

Very small sample (n=22) of regular users who may have tolerance. Naturalistic dosing means no placebo control. Participants knew they were taking cannabis, so expectancy effects cannot be ruled out. The relatively low average dose (7.3 mg) may not reflect all consumer patterns.