Comparison of Caffeine and Music as Fatigue Countermeasures in Simulated Driving Tasks

Abstract

Driver fatigue is a leading cause of traffic accidents. Appropriate fatigue countermeasures can help drivers prevent operational errors and improve road safety. A review of the literature has suggested that consuming caffeine and listening to music are two commonly adopted fatigue countermeasures. This paper examines effects of the two fatigue countermeasures on subjective fatigue levels and driving performance. Differences between the two methods are also investigated. Twenty participants completed three 120-minute control, caffeine, and music sessions at the same time on three days. Subjective fatigue levels were quantified using a subjective driver fatigue score, and driving performance was measured using 16 parameters related to vehicle control ability. Initially, there were no significant differences in subjective fatigue and driving performance among three sessions. The final subjective driver fatigue score for caffeine and music sessions was significantly lower than control sessions, suggesting both inhibited subjective fatigue increase. The increment in driving performance parameters for caffeine sessions was significantly less than control and music sessions, but not significantly different between control and music sessions. Caffeine is more effective than music in inhibiting driving performance deterioration; because caffeine stimulates the central nervous system; on the other hand, music only reduces boredom and may introduce additional distraction to the driver.