11/5/2008 · Kategori:
Why/Neden?
Why sleep is important and what happens when you don't get enough?
Importance of sleep
Sleep is essential for a person’s health
and wellbeing, according to the National Sleep Foundation (NSF). Yet
millions of people do not get enough sleep and many suffer from lack of
sleep. For example, surveys conducted by the NSF (1999-2004) reveal
that at least 40 million Americans suffer from over 70 different sleep
disorders and 60 percent of adults report having sleep problems a few
nights a week or more. Most of those with these problems go undiagnosed
and untreated. In addition, more than 40 percent of adults experience
daytime sleepiness severe enough to interfere with their daily
activities at least a few days each month - with 20 percent reporting
problem sleepiness a few days a week or more. Furthermore, 69 percent
of children experience one or more sleep problems a few nights or more
during a week.
What are the signs of excessive sleepiness?
According
to psychologist and sleep expert David F. Dinges, Ph.D., of the
Division of Sleep and Chronobiology and Department of Psychiatry at the
University of Pennsylvania School of Medicine, irritability, moodiness
and disinhibition are some of the first signs a person experiences from
lack of sleep. If a sleep-deprived person doesn’t sleep after the
initial signs, said Dinges, the person may then start to experience
apathy, slowed speech and flattened emotional responses, impaired
memory and an inability to be novel or multitask. As a person gets to
the point of falling asleep, he or she will fall into micro sleeps(5-10
seconds) that cause lapses in attention, nod off while doing an
activity like driving or reading and then finally experience hypnagogic
hallucinations, the beginning of REM sleep. (Dinges, Sleep, Sleepiness
and Performance, 1991)
Amount of sleep needed
Everyone’s
individual sleep needs vary. In general, most healthy adults are built
for 16 hours of wakefulness and need an average of eight hours of sleep
a night. However, some individuals are able to ******** without
sleepiness or drowsiness after as little as six hours of sleep. Others
can't perform at their peak unless they've slept ten hours. And,
contrary to common myth, the need for sleep doesn't decline with age
but the ability to sleep for six to eight hours at one time may be
reduced. (Van Dongen & Dinges, Principles & Practice of Sleep
Medicine, 2000)
What causes sleep problems?
Psychologists
and other scientists who study the causes of sleep disorders have shown
that such problems can directly or indirectly be tied to abnormalities
in the following systems:
Physiological systems
Brain and nervous system
Cardiovascular system
Metabolic ********s
Immune system
Furthermore, unhealthy conditions, disorders and diseases can also cause sleep problems, including:
Pathological sleepiness, insomnia and accidents
Hypertension and elevated cardiovascular risks (MI, stroke)
Emotional disorders (depression, bipolar disorder)
Obesity; metabolic syndrome and diabetes
Alcohol and drug abuse
(Dinges, 2004)
Groups
that are at particular risk for sleep deprivation include night shift
workers, physicians (average sleep = 6.5 hours a day; residents = 5
hours a day), truck drivers, parents and teenagers. (American Academy
of Sleep Medicine and National Heart, Lung, and Blood Institute Working
Group on Problem Sleepiness. 1997).
http://www.apa.org