ABSTRACT
ABSTRACT: Human operators need to keep high vigilance in many tasks. Sleep loss often induces decreased vigilance, while the time of day may modulate the effects of sleep loss on human vigilance. The current study aims to investigate the effects of sleep restriction and circadian rhythm on human vigilance. The Psychomotor Vigilance Task (PVT) metrics are selected as objective measures of human vigilance. The constant routine procedure in circadian rhythm research is adopted in our experimental study: in the days with sleep restriction, participants are restricted to 5 hours of sleep; in the control days, participants are allowed to sleep 8 hours per day. The participants are required to perform the PVT test repeatedly at different times of the day (in the morning, at noon, in the afternoon, in the evening and at midnight). The results show that in the sleep restriction condition, the PVT metrics of the participants are significantly worse. Meanwhile, the vigilance of the participants is shown to be significantly better in the afternoon and in the evening than in the morning and at noon.
