Simulated Driving Performance of Inexperienced and Experienced Drivers After Single Doses of Cannabis, Alcohol and Their Combination

The present experiment compared the effects of three doses of cannabis and alcohol, both alone and in combination, on driving performance in young, novice drivers and more experienced drivers. Alcohol was administered as ethanol (95%) mixed with orange juice in doses of approximately 0.4 and 0.6 g/kg, which produced peak blood alcohol concentrations generally under 0.05%. Cannabis was administered by inhalation of smoke from pre-rolled cannabis cigarettes (supplied by the National Institute of Drug Abuse, USA). Each cigarette contained 19mg delta-9-THC. All participants were tested under nine drug conditions with a counterbalanced design. The study involved five different driving scenarios in the MUARC driving simulator: Arterial, Rural, Residential, Freeway, and Risk Perception drives. This report presents some data from the arterial drive. Both alcohol and cannabis separately were associated with increases in the standard deviation of lateral position (SDLP), which is consistent with previous research. The effects of the drugs in these alternate driving environments are currently being examined