Page:Risk of performance errors due to sleep loss, circadian desynchronization, fatigue, and work overload.pdf/8

Chapter 3. Subjects who spent 3 hours in bed reached levels of severe impairment at 5 days, while subjects who spent 5 hours in bed reached levels of impairment at 4 days.

These Category I laboratory studies by Van Dongen et al. (2003) and Belenky et al. (2003) clearly show that subjects suffered performance impairments resulting from total sleep deprivation and/or chronic sleep restriction.