This is the 2007 version. Click here for the 2017 chapter 03 table of contents.

Sleep Deprivation

The effects of sleep deprivation are not as severe as once thought. Most people can pull an "all-nighter" (stay up one night) with no ill effects other than extreme sleepiness. But most people have trouble staying up for more than 48 hours. Long walks, exposure to cold, and attention-grabbing stimuli will keep a person awake after 48 hours, but after 100 hours (4 days) only constant prodding from an experimenter will keep people from dozing off.

What happens as the amount of sleep deprivation increases?

Many studies show that subjects can compensate well for the effects of sleep deprivation. However, the number of mental lapses increases steadily as the amount of sleep deprivation increases. These mental lapses are moments when a person does not respond to a signal from the experimenter or "drifts off" and forgets to concentrate on an assigned task. Webb (1981) called these "involuntary rest periods." Others call them microsleeps

What pattern emerged in a British study of sleep deprivation, and how might it explain students yawning in lecture classes?

Researchers in Britain kept a group of young adults awake for three days and studied their performance on a variety of laboratory tasks requiring problem-solving ability, memory, motor coordination, and vigilance (ability to maintain concentrated attention). An interesting pattern emerged. The only tasks that proved difficult after losing a night of sleep were boring tasks. With intellectually challenging or physically demanding tasks, subjects showed no effect of sleep deprivation. When subjects had to press a button every minute or so when they heard a soft tone, which was a boring task, they kept drifting off.

Unfortunately, when a person is sleep deprived, events are more likely to seem boring. A person with no sleep deprivation "will probably not fall asleep even in the most boring of lectures" according to sleep researchers (Adler, 1993). However, a person deprived of sleep is likely to find the same lecture boring, and that person may get almost uncontrollably sleepy during a lecture.

How did the experiences of Tripp and Gardner contrast?

Only a handful of people have remained awake over 200 hours (8 days). A famous case is that of Peter Tripp, a New York disk jockey, who vowed to stay awake for 200 hours to raise money for the March of Dimes. He was closely monitored by sleep researchers and tested in various ways. By 100 hours he was already hallucinating. Tripp managed to finish his 200-hour ordeal, slept for 13 hours, and awoke feeling normal, although he reported a slight depression that lasted for three months afterward. Tripp's hallucinations may have been due to amphetamine drugs he was taking (under the supervision of doctors) to keep himself awake.

Five years later, a young man named Randy Gardner tried to break the world record for sleeplessness. While sleep researchers observed him and monitored his body functions, he went over 260 hours without any drugs or any ill effects except occasional mental lapses. Unlike Peter Tripp, he experienced no hallucinations. He slept fourteen and a half hours after his sleepless period and seemed normal after that.

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