ABSTRACT
The essential need for sleep in order to behave and feel 'normal' is known across cultures and time. A mediaeval man in England who had served the years of preparation as a squire to become knighted had to spend the night before the final ceremony kneeling, awake, in vigil to prove himself able for the honour and duty of a knight. The very final consequences of sleep deprivation in non-human animals are not necessarily shown in humans, but then human research participants are treated differently. Many studies have been done involving depriving human participants of some or all sleep and, though a temporary degree of dysfunction has sometimes resulted, this has not been life-threatening or, of course, the study would have been stopped at an early stage.
