This paper presents some further results and gives some additional details of the study described in the previous abstract. The over-the-road driving test consisted of operating an instrumented vehicle over a 100km circuit (50km in each direction) of a primary road in each direction, while attempting to maintain a constant speed of 90kph and a steady lateral position within the right traffic lane. The simulator comprised a car seat, a steering wheel and two brake pedals. There was a signal display with two horizontal arrays of lamps in front of the seat. The main tracking task was to react appropriately to a random signal in the upper array by moving the steering wheel. The primary performance parameter of the driving test was the standard deviation of lateral position (SDLP). The parameters of the simulator test were the reaction time (RT) and the number of correctly executed tracking control manoeuvres (TC). The test duration was 30min, and the subjects received full training beforehand. Neither drug significantly affected the simulator driving performance. However, oxazepam 50mg seriously impaired the over-the-road driving performance on both mornings, though not in the afternoon of the second test day. Lormetazpam 1mg produced no significant effects.
Samenvatting