Aurora, CO: Daily cannabis consumers exhibit fewer changes in performance than do those who use it less frequently, according to data published in the Journal of Cannabis Research.
A team of investigators affiliated with the University of Colorado and the University of Iowa assessed changes in performance in a cohort of daily versus occasional cannabis consumers. Participants inhaled high-THC flower (15 to 30 percent THC) ad libitum. Researchers compared subjects’ baseline performance to their performance one hour after smoking.
Consistent with prior research, the study’s authors concluded: “In two of the tablet-based tasks, the occasional use group performed slower (reaction time task) or less accurately (memory task) from before to after smoking, as compared to daily use and no-use groups, consistent with daily cannabis use resulting in tolerance to the acute effects of cannabis. In the gap acceptance task, the daily use group took longer to complete the task after smoking cannabis, while at the same time increasing their success ratio.
“Taken together, the findings are consistent with acquired tolerance to certain acute drug effects. The increase in time that the daily use group required to complete the gap acceptance task may nonetheless indicate an acute effect of cannabis among those in the daily use group, who prioritized accuracy over response time. Psychomotor and cognitive assessment batteries, such as the one used in this study, hold promise for providing an objective measure of cannabis impairment.”
NORML opposes the imposition of per se THC thresholds for motorists and alternatively calls for the expanded use of mobile performance technology like DRUID to determine whether someone is under the influence.
Full text of the study, “Effects of acute cannabis inhalation on reaction time, decision-making, and memory using a tablet-based application,” appears in the Journal of Cannabis Research. Additional information is available from the NORML Fact Sheet, ‘Marijuana and Psychomotor Performance.’