Effects of Sleep Deprivation on Vigilance, Attention, and Performance During Simulated Train Driving

Abstract

Sleep deprivation has been cited as a major factor that plays an important role in many incidents in the transportation sector. Sleep-deprived train drivers is a fairly common phenomenon in Indonesia, with local reports indicating a good percentage of train drivers who are sleep deprived prior to work. The present study was aimed at quantifying the effects of sleep deprivation on alertness and performance during prolonged simulated train driving. A total of 12 subjects participated in this study and were asked to sleep for approximately 2 h (sleep deprived) and 8 h (normal sleep) the night before the experimental day. The experiment consisted of driving a train simulator for 4 h on a monotonous route. Fatigue and sleepiness were assessed using Psychomotor Vigilance Task (PVT) and Sustained Attention Test (SAT), conducted before and after the driving simulation. Subjective levels of fatigue and sleepiness were determined using questionnaires, while driving performance was measured based on the number of speed-limit violations. Results of this study showed that two hours of sleep was characterized with an initial subjective fatigue and sleepiness measures that were up to two to three times greater than the normal sleep condition. This condition also resulted in poorer driving performance (75% increase in the number of speeding error). While the effects of sleep deprivations on the performance of train driving is probably obvious, the quantitative effects have not been addressed extensively in the literature. It is concluded in this study that the effects of excessive sleep deprivation on fatigue and sleepiness varies, depending on the measures used.