Yale Center for the Science of Cannabis and Cannabinoids

The February 2026 YC-SCAN2 webinar Driving While Stoned: Why It’s Complicated, featured Godfrey Pearlson, who presented a comprehensive overview of cannabis and driving impairment. His talk examined the pharmacokinetics and pharmacodynamics of THC, its behavioral effects on driving performance, and the broader public health implications of cannabis use behind the wheel. Dr. Pearlson highlighted the unique challenges in detecting cannabis-related impairment compared to alcohol, noting the limitations of current roadside sobriety testing and per se legal standards. Drawing on his research using advanced driving simulators and virtual reality paradigms, he demonstrated that THC can impair critical driving skills in subtle but meaningful ways, with effects that may persist even after blood THC levels decline. The presentation also addressed the complexity of cannabis use patterns, including variability across dosage forms and the absence of a standardized dose equivalent, and emphasized the need for continued research on issues such as edible cannabis and sex-related differences in impairment.