Samenvatting
the phenomenon of drowsiness and sleep during vehicle operation was first studied by noting the normal occurrence of sleep for three male and three female subjects, aged 18-25, in an appropriate environment. The subjects were then tested for drowsiness while performing a simulated driving task. As an individual passes through the stages of wakefulness and sleep, many psychological variables change. The electroencephalographic and skin potential changes as related to wakefulness and sleep are reported.