A six-hour time series of the acute effects of ingested cannabis intoxication on a battery of cognitive tasks

As ≥33% of Canadian adults used cannabis last year, characterizing the effects of acute cannabis intoxication on cognitive function is imperative. The effects of inhaled cannabis intoxication on several cognitive tasks are well known; however, ≥50% of cannabis users consumed ingestible cannabis products (i.e., ‘edibles’) in 2023, for which the cognitive effects are poorly understood. Edible intoxication likely presents differently from inhalation due to different absorption and metabolic routes for the psychoactive component of cannabis, Δ9-tetrahydrocannabinol (THC). Thus, the purpose of our study was to characterize the acute effects of ingested cannabis intoxication on cognitive function. Fourteen participants (8 female; 29.7±7.3years), who had consumed cannabis before, but not more than once per week in the six months prior to participation, performed a battery of cognitive tasks before (baseline; BL) as well as immediately (0h), 0.5h, 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 5h, and 6h following ingestion of two 5mg THC capsules. The battery included simple reaction time (SRT), go/no go reaction time (GNG), Corsi block tapping (CBT), visuospatial trail making (VTM), and a subjective questionnaire. Outcomes at each timepoint were compared to BL. Participants felt intoxicated 1-6h post-ingestion. SRT and SRT variability were increased from 2.5-3.5h and 3-4h, respectively. GNG accuracy was reduced from 1h-6h, and VTM errors were greater at 2h (all p