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Your Guide to Sleep Disorders.
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Sleep debt can be measured in a number of ways. An objective measure of a person's sleep debt would be the Multiple Sleep Latency Test (MSLT). The test operates through qualitative observations of the speeds of falling asleep during the day. As an analogy, a very thirsty person will gulp down a glass of water within seconds, while a sleep deprived person will fall asleep within a minute. The lower the sleep latency, or the amount of time it takes for a wide awake person to fall asleep, the higher the sleep debt. An easier way to measure one's sleep debt is simply observing whether one becomes sleepy during the day. This is largely caused by a substantial sleep debt.

Surveys conducted by sleep researcher Dr. William Dement of Stanford University, hailed to be the "father of sleep", reveal that about 90% of adults believe that a heavy lunch causes them to feel drowsy and induces sleep. This is a blatantly erroneous claim. With a small sleep debt, one does not become drowsy after lunch. However, a large sleep dept contributes to low alertness levels during mid-afternoon regardless of one's lunch consumption. Other indicators of a large sleep debt include reduced concentration levels, difficulty in waking up in the morning, low motivation levels, and a predisposition to irritable conduct.

In addition to the above misconception, other common erroneous claims include attributing a warm room, monotony, boredom, and alcoholic beverages as direct causes of sleepiness. The truth is: none of the listed factors causes sleepiness. Instead, they unmask and reveal the size of one's sleep debt. A person with a relatively low sleep debt will not become sleepy from lunch, alcohol or boredom.

Apart from directly affecting our daily lifestyles, the lack of understanding of the importance of sleep has even greater repercussions: a large sleep debt increases our vulnerability to errors, injuries, accidents, catastrophes and death. Stories of college students who fell asleep at the wheel are often overshadowed by tales of those who drove home drunk. Yet, they merit equal attention, if not more. Tragedies such as 1979 the Three Mile Island meltdown, the 1986 launching of the Challenger and Chernobyl nuclear accident, and the 1989 Exxon Valdez oil spill are attributable to sleep-deprived operators. It is therefore imperative to raise current low levels of public and professional awareness of sleep.

Many people ignorantly attempt to find sleep substitutes such as coffee. This is futile, as in doing so, they merely intensify the effects of existing sleep deprivation and aggravate other health problems. Sleep debt does not dissipate and can only be reduced and alleviated through extra sleep. All wakefulness is sleep deprivation. By paying off an individual's sleep debt, one will become healthier and will be able to lead a desirable and healthy lifestyle.