Comparative sensitivity of a simulated driving task to self-report, physiological, and other performance measures during prolonged wakefulness.

OBJECTIVES The objectives of this study were to compare (1) the sensitivity of simulated driving to self-report measures, nocturnal sleep latency tests (SLTs), and an auditory vigilance task and (2) urban and motorway driving. METHODS Healthy males 18 to 35 years maintained wakefulness for one night and were tested at 2400, 0230, 0500 and 0730 h. In Study 1 (n=11), the SLTs were followed by auditory vigilance and simulated driving tasks; in Study 2 (n=18), the SLTs were preceded and followed by simulated driving on motorway and urban routes. RESULTS In Study 1, speed variability, tracking variability, and driving off the road on the driving simulator had comparable sensitivity to d' on the auditory vigilance task. In Study 2, driving performance was consistently worse on the motorway route. CONCLUSION The driving simulator was equally sensitive to another performance measure during prolonged wakefulness and impairments were greater with motorway driving.