|
 |
 |
Sleep |
 |
|
|
|
|
|
Info: Biography, Pictures, Discography of all CDs & DVDs |
|
| For other uses, see Sleep (disambiguation).Sleep is the natural state of bodily rest observed throughout the animal kingdom, in all mammals and birds, and in many reptiles, amphibians, and fish.While sleep is essential for survival, its purposes are only partly clear and are the subject of intense research.Stages of sleep
1.Effect of food and drink on sleep
7.Longest period without sleep (trivia)
9 See also
9.Practices and rituals
9.This section needs additional citations for verification.Each type has a distinct set of associated physiological, neurological and psychological features.Sleep proceeds in cycles of REM and the four stages of NREM.Drugs such as alcohol and sleeping pills can suppress certain stages of sleep (see Sleep deprivation).This can result in a sleep that exhibits loss of consciousness but does not fulfill its physiological functions.Rechtschaffen and Kales originally outlined the criteria for staging sleep in 1968.The American Academy of Sleep Medicine (AASM) updated the staging rules in 2007.In NREM sleep, there is relatively little dreaming.This stage is sometimes referred to as somnolence, or "drowsy sleep".Associated with the onset of sleep during N1 may be sudden twitches and hypnic jerks.Some people may also experience hypnagogic hallucinations during this stage, which can be more troublesome to the subject.During N1 the subject loses some muscle tone, and conscious awareness of the external environment.During this stage, muscular activity as measured by electromyography (EMG) lowers and conscious awareness of the external environment disappears.In Stage N3, the delta waves, also called delta rhythms (0.SWS) and appears to function primarily as a transition into stage N4.Both REM sleep and NREM sleep stages 3 and 4 are homeostatically driven; that is, if a person or animal is selectively deprived of one of these, it rebounds once uninhibited sleep again is allowed.This suggests that both are essential to the functions of the sleep process.Adenosine is created over the course of the day; high levels of adenosine lead to sleepiness.In diurnal animals, sleepiness occurs as the circadian element causes the release of the hormone melatonin and a gradual decrease in core body temperature.The timing is affected by one's chronotype.It is the circadian rhythm which determines the ideal timing of a correctly structured and restorative sleep episode.Homeostatic sleep propensity, the need for sleep as a function of the amount of time elapsed since the last adequate sleep episode, is also important and must be balanced against the circadian element for satisfactory sleep.Along with corresponding messages from the circadian clock, this tells the body it needs to sleep.Sleep offset, awakening, is primarily determined by circadian rhythm.People with some circadian rhythm sleep disorders are an exception.Adults
The optimal amount of sleep is not a meaningful concept unless the timing of that sleep is seen in relation to an individual's circadian rhythms.University of Pennsylvania School of Medicine demonstrated that cognitive performance declines with fewer than eight hours of sleep.Children need a greater amount of sleep than adults to function correctly (up to 18 hours for newborn babies, with a declining rate as the child ages).During pregnancy, women may need more sleep per night.Sleep debt
Main article: Sleep debt
Sleep debt is the effect of not getting adequate sleep; a large debt causes mental and physical fatigue.Scientists do not agree on how much sleep debt it is possible to accumulate, nor on whether the prevalence of sleep debt among adults has changed appreciably in the industrialized world in recent decades.It is likely, however, that children are sleeping less than they used to in western societies.Functions
The multiple theories proposed to explain the function of sleep are reflective of the as yet incomplete understanding of the subject.It is likely that sleep evolved to fulfill some primeval function, but has taken over multiple functions over time as organisms have evolved.All of these are its functions but just one of them likely represents the original function.Restoration
Wound healing has been shown to be affected by sleep.It has yet to be clearly proven that sleep duration affects somatic growth.There are multiple arguments supporting the restorative function of sleep.We feel rested after sleeping, and it is natural to assume that this is the basic purpose of sleep.Overall metabolic rate goes down during sleep and certain anabolic hormones such as growth hormones as mentioned above are secreted preferentially during sleep.Animals with greater need to conserve energy sleep more.Sleep among species in inversely related to the animal size and Basal metabolic rate.Energy saved by sleeping for eight hours in a sedentary 200 lb male is about what we get from a cup of milk.Additionally, there is no convincing evidence that ATP stores are replenished during sleep.Unihemispheric sleep occurs in aquatic mammals even when they are actively swimming about, and probably in migratory birds also while they are flying.Sleep therefore does something else other than conserving energy.Most interestingly, hibernating animals, when they wake up from hibernation go into rebound sleep because of lack of sleep during the hibernation period.They are definitely well rested and are conserving energy during the hibernation, but need sleep for something else.REM sleep may be an anabolic state marked by physiological processes of growth and rejuvenation of the organism's immune, nervous, muscular, and skeletal systems (but see above).Ontogenesis
According to the ontogenetic hypothesis of REM sleep, the activity occurring during neonatal REM sleep (or active sleep) seems to be particularly important to the developing organism (Marks et al.Studies investigating the effects of deprivation of active sleep have shown that deprivation early in life can result in behavioral problems, permanent sleep disruption, decreased brain mass (Mirmiran et al.REM sleep appears to be important for development of the brain.REM sleep occupies majority of time of sleep of infants, which spend most of their time sleeping.Among different species, more immature the baby is born, more time it spends in REM sleep.However, this does not explain why older adults still need REM sleep, and why the fraction of time spent does not change significantly as one ages.Aquatic mammal infants do not have REM sleep in infancy.REM sleep in those animals increases as they age.Obviously, REM sleep is not needed for development in these animals.This article or section contains too much jargon and may need simplification or further explanation.Scientists have shown numerous ways in which sleep is related to memory.Subjects were given initial cognitive tests while well rested and then tested again twice a day during the 4 days of sleep deprivation.This demonstrates that there is clearly a connection between sleep and memory.Sleep and wake groups were taught a task and then tested on it both on early and late nights, with the order of nights balanced across participants.The subjects chosen were 22 male rats.The bottom of the box was made of a steel grate.The length of the shock never exceeded 5 seconds.REM sleep after learning trials than after control trials.REM sleep and procedural knowledge.The different studies all suggest that there is a correlation between sleep and the many complex functions of memory.Preservation
The "Preservation and Protection" theory holds that sleep serves an adaptive function.They sleep at times that maximize their safety, given their physical capacities and their habitats.However, this theory fails to explain why the brain disengages from the external environment during normal sleep.Another argument against the theory is that sleep is not simply a passive consequence of removing the animal from the environment, but is a "drive": animals alter their behaviors in order to obtain sleep.Therefore, circadian regulation is more than sufficient to explain periods of activity and quiescence that are adaptive to an organism, but the more peculiar specializations of sleep probably serve different and unknown functions.Moreover, the preservation theory does not explain why carnivores like lions, which are on top of the food chain, sleep the most.By the preservation logic, these top carnivores should not need any sleep at all.Preservation does not explain why aquatic mammals sleep while moving.Lethargy during these vulnerable hours would do the same, and will be more advantageous because the animal will be quiescent but still be able to respond to environmental challenges like predators etc.Sleep rebound that occurs after a sleepless night will be maladaptive, but still occurs for a reason.For example, a zebra feeling falling asleep the day after it spent the sleeping time running from a lion is more and not less vulnerable to predation.Causes of difficulty sleeping
There are a great many possible reasons for sleeping poorly.Following sleep hygienic principles may solve problems of physical or emotional discomfort.Elderly people may to some degree lose the ability to consolidate sleep.They need the same amount per day as they've always needed, but may need to take some of their sleep as daytime naps.Dreaming is stimulated by the pons and mostly occurs during the REM phase of sleep.See Freud:The Interpretation of Dreams
James Allan Hobson's and Robert McCarley's activation synthesis theory proposes that dreams are caused by the random firing of neurons in the cerebral cortex during the REM period.According to the theory, the forebrain then creates a story in an attempt to reconcile and make sense of the nonsensical sensory information presented to it, hence the odd nature of many dreams.This is most often experienced by pubescent boys during REM sleep, but may occur at any time after puberty.Anthropology of sleep
Recent research suggests that sleep patterns vary significantly across human cultures.The most striking differences are between societies that have plentiful artificial light and ones that do not.This is called polyphasic sleep or segmented sleep and has led to expressions such as "first sleep," "watch," and "second sleep" which appear in literature from all over the world.Some cultures have fragmented sleep patterns in which people sleep at all times of the day, and for shorter periods at night.For example, many Mediterranean and Latin American cultures have a siesta, in which people sleep for a period in the afternoon.Uberman's sleep schedule, which involve sleeping in regular patterns of 20 minute sleep and 4 hours awake, leading to greatly increased wake time.Such patterns purportedly lead to the body's ability to jump instantly into the most necessary sleep stages.These people sleep in a concentrated burst at night, and sleep later in the morning.Cattle, horses, and sheep can sleep while standing or while lying down; however, they cannot experience REM sleep while standing.If deprived of REM sleep for a long time, the animal may involuntarily collapse in order to reach REM sleep, a condition not to be confused with narcolepsy.Sleep becomes difficult to define in lower order animals, such as the bullfrog.Its resting state is too similar to its active state to be considered by many to satisfy the criteria for sleep, but brain activity in the resting state is similar to other amphibians that do meet the criteria when they sleep.Also, on average, larger mammals tend to spend much less time in sleep than smaller mammals.Small animals are often preyed on by larger animals, so they may sleep less in order to minimize the risk of being attacked.Drowsiness
Tryptophan
Some foods contain an amino acid called tryptophan that causes sleepiness.Melatonin
Melatonin is a naturally occurring hormone that regulates sleepiness.It is made in the brain by converting tryptophan into serotonin and then into melatonin, which is released at night by the pineal gland in the brain to induce and maintain sleep.Alcohol
Alcohol is commonly used as a sleep aid, however, it is not a good aid for sleep because although it helps one relax and fall asleep in the short term, it often disrupts sleep throughout the night and can keep one from entering the deeper stages of sleep, which can cause one to wake up tired regardless of having spent a proper amount of time asleep.Stimulation
Caffeine
Caffeine is a stimulant that works by slowing the action of the hormones in the brain that make us feel sleepy.Longest period without sleep (trivia)
Depending on how one defines sleep, there are several people who can claim the record for having gone the longest without sleep.Randy Gardner holds the Guinness World Record for intentionally having gone the longest without sleep.He experienced significant deficits in concentration, motivation, perception and other higher mental processes during his sleep deprivation.However, he recovered normal cognitive functions after a few nights' sleep.The Guinness Book of Records has, however, withdrawn its backing of a sleep deprivation class because of the associated health risks.There have been various, though largely unsubstantiated, claims by methamphetamine users that with the aid of methamphetamine they have gone without sleep for periods of up to two weeks.Waking Up To Sleep (Several conference videos).Heather Larson, Gina Kemp, M.Understanding Sleep: Sleep Needs, Cycles, and Stages.Experts challenge study linking sleep, life span.Understanding Sleep: Sleep Needs, Cycles, and Stages.Jenni, MD, Luciano Molinari, PhD and Remo H."Sleep Duration From Infancy to Adolescence: Reference Values and Generational Trends".Thus, the shift in the evening bedtime across cohorts accounted for the substantial decrease in sleep duration in younger children between the 1970s and the 1990s.What Causes Sleep Difficulty?.Toward a comparative developmental ecology of human sleep", A comparative developmental ecology (PDF), Emory University."Interhemispheric asymmetry of the electroencephalographic sleep patterns in dolphins".Re: Are there animals who don't sleep or that sleep very little?."Chapter 3", Dynamics of Complex Systems (PDF)."Sleep and epilepsy: what we know, don't know, and need to know."."Mechanisms of arousal from sleep and their consequences."."Association of sleep time with diabetes mellitus and impaired glucose tolerance."."Sleep and hypertension: a challenge for the autonomic regulation of the cardiovascular system.".Changes in sleep cycle patterns with age J Psychiatr Res.Normal age related changes in sleep.Sleep Disorders: Basic and Clinical Research."Active sleep and its role in the prevention of apoptosis in the developing brain.".REM sleep in brain maturation."."Effects of experimental suppression of active (REM) sleep during early development upon adult brain and behavior in the rat.".Journal of Theoretics 6 (6).Look up Sleep in
Wiktionary, the free dictionary.All text is available under the terms of the GNU Free Documentation License.Some sleep disorders are serious enough to interfere with normal physical, mental and emotional functioning.Common sleep disorders
The most common sleep disorders include:
Bruxism: The sufferer involuntarily grinds or clenches his or her teeth while sleeping.Delayed sleep phase syndrome (DSPS): A sleep disorder of circadian rhythm, characterized by the inability to wake up and fall asleep at the desired times, but not by inability to stay asleep.Hypopnea syndrome: Abnormally shallow breathing or slow respiratory rate while sleeping.Narcolepsy: The condition of falling asleep spontaneously and unwillingly at inappropriate times.Night terror or Pavor nocturnus or sleep terror disorder: abrupt awakening from sleep with behavior consistent with terror.See also Hypnic jerk, which is not a disorder.Shift work sleep disorder (SWSD).Sleep apnea: The obstruction of the airway during sleep, causing loud snoring and sudden awakenings when breathing stops.Sleepwalking or somnambulism: Engaging in activities that are normally associated with wakefulness (such as eating or dressing), which may include walking, without the conscious knowledge of the subject.Snoring: Loud breathing patterns while sleeping; sometimes this is a symptom of sleep apnea.Bedwetting or sleep enuresis.Common causes of sleep disorders
Changes in life style, such as shift work change (SWC), can contribute to sleep disorders.Many drugs can affect the ratio of the various stages of sleep, thus affecting the overall quality of sleep.Poor sleep can lead to accumulation of Sleep debt.Chronobiological disorders, mainly Circadian rhythm disorders
A sleep diary can be used to help diagnose, and measure improvements in, sleep disorders.William Dement, of the Stanford Sleep Center, anyone who snores and has daytime drowsiness should be evaluated for sleep disorders.Any time back pain or another form of chronic pain is present, both the pain and the sleep problems should be treated simultaneously, as pain can lead to sleep problems and vice versa.None of these general approaches is sufficient for all patients with sleep disorders.Rather, the choice of a specific treatment depends on the patient's diagnosis, medical and psychiatric history, and preferences, as well as the expertise of the treating clinician.In general, medications and somatic treatments provide more rapid symptomatic relief from sleep disturbances.Some sleep disorders, such as narcolepsy, are best treated pharmacologically, whereas others, such as chronic and primary insomnia, are more amenable to behavioral interventions.The management of sleep disturbances that are secondary to mental, medical, or substance abuse disorders should focus on the underlying conditions.This page was last modified 08:01, 22 January 2008.All text is available under the terms of the GNU Free Documentation License.See Copyrights for details.How much sleep is enough?Why sleep is good for you and skimping on sleep isn't
How much sleep do you need?Tips for a good nights sleep
Could you have a sleep disorder?Are You Sleep Deprived?Individuals vary in their need for sleep.Are you getting enough sleep?How much sleep is enough?Some people believe that adults need less sleep as they get older.Read about the medication zolpidem (Ambien), a drug used as a sleeping pill to treat insomnia.Source:MedicineNet
Read 662 more Sleep related articles ...Get tips for better sleep.From Apply Now,Your Guide to Sleep Disorders.Extraverts More Sleep Deprived
Extroverts have outgoing personalities and are more excitable and more easily bored than introverts.After one night of no sleep, introverts suffered less from the effects of sleep deprivation than extroverts.As more data is collected on this factor in predicting the impact of sleep deprivation, it may be important to certain industries that rely on long periods of wakefulness (like the military or certain manufacturing industries).Seniors Suffering From Sleep Problems
As people age, getting enough sleep becomes more and more challenging.Add to this the side effects of some medications and you have a recipe for sleep problems.Seniors tend to wake up frequently during the night and get less REM (or dream) sleep.If you are having trouble getting enough quality sleep, ask your doctor to recommend a sleep specialist to help solve this serious medical problem.Sleepless Nights Predict Sick Days
We know that illness and sleep problems are related.In this study, researchers had the clever idea of looking at the number of sick days a person took and comparing that to their sleep quality.Researchers examined 8300 individuals and gave them a survey about their sleep habits.It turns out that people who reported having problems sleeping had more sick days two years later.Does lack of sleep cause illness?Sleep problems may have been a sign of illness building up.However, aggressively treating sleep problems would certainly help to decrease the duration and severity of some types of illness.Yet another reason to take care of sleep issues quickly.Sleep Problems Common in Parkinson's Disease
Parkinson's disease is a disease of the brain associated with aging.One thing that often happens during Parkinson's disease is that people have trouble sleeping.European Journal of Neurology examined the sleep habits of 122 Parkinson's disease patients.The most common problems were sleep fragmentation (sleep being broken in many segments) and nocturia (nighttime urination).This research will help to call attention to this complication of Parkinson's disease and help patients and caregivers solve the problem of sleep.Turns out that insomnia has a large number of causes and signs.What about if you can't sleep for two weeks?When does "having trouble sleeping" become the medical condition "insomnia?"Melatonin is necessary to fall asleep quickly and stay asleep.It claims that there is not yet research on whether this approach works.While this finding may seem obvious, what this study was able to do was put some concrete numbers behind the common sense conclusion.All the nurses reported problems in getting enough sleep when working these long shifts.Restless Legs and Heart Disease Linked
A study observed 1550 men and 1874 women with an average age of 68 years for connections between sleep disorders and heart disease.Sleep Meds Increase Hospital Stay in the Elderly
A study looked at the use of sleep medications for elderly patients in the hospital.When looking at these number, you should remember that patients needing sleep medications may have more complicated illnesses.Cholesterol ResourcesManage Your CholesterolWhich Fats Are Healthy?Cholesterol QuizLow Cholesterol DietCholesterol Podcast What's HotSleep Deprived StudentsBruxismStress Related InsomniaNightmares and Night TerrorsDreams That Terrify
if(!Be a GuideMore from About, Inc.The New York Times Company.Aren't They Precious When They're Asleep?Sleep Deprivation And ADHD
ADHD and Snoring
Smoking, Snoring and ADHD?Tonsillectomy for Behavior Problems?Tonsils Out to Treat ADHD?Adolescents and Sleep
Sleep Terrors, Sleepwalking and Bedwetting: The Effect of Naps
Snoring, Memory, Attention, and Learning
Side Effects of Ritalin
Snoring And Sleep Apnea
Tonsillectomy for Behavior Problems?Tonsillectomy for Behavior Problems?Sleeplessness
Why Does My Child Always Seem to Get Sick At Night?SIDS and Sleeping Arrangements
SIDS Prevention and Flat Heads
Misshapen Heads Due To Back Sleeping
Baby Waking At Night?How Much Sleep is Needed?Swaddling
Swaddling and Sleep
Sleep Patterns
Change in Sleep Patterns
Infant Sleep Changes
Baby Waking At Night?The Truth About Dreams, Nightmares, and Night Terrors
Night Terrors
What Are Night Terrors?If you are experiencing problems viewing this website, contact the webmaster.Copyright 2008 Greene Ink, Inc.Disclaimer, Limitations, Revisions, and Errata.Notice: All pages and their content are provided as information only.This is not a substitute for medical care or your doctor's attention.Please seek the advice of your pediatrician or family doctor.The heart of Sleepnet.This is an educational site devoted to improving sleep health worldwide.Disclaimer:
The information provided by Sleepnet.If you suspect that you have a sleep disorder you should seek care from a qualified professional.Sleep is a beautiful word and an exciting concept especially to those who suffer from insomnia.The brain in particular is sending out all sorts of signals, many of which are controlling the various stages of sleep you'll be
undergoing.There are several known characteristics of sleep...There are five stages of sleep which have been identified and on a good night's sleep you pass through all of them, several times.The different sleep stages are distinguished by the changes in brain wave activity that takes place.NREM and REM sleep take place throughout the sleep period.The sleep that takes place during the first third of a night consists mostly of
NREM while the sleep during the last third is mostly REM.It consists of light sleep from which you can easily be awakened.During this stage, a sudden
contraction or jerking of muscles can happen.During this stage the eyes stop moving, brain waves slow, body temperature drops and
heart beat slows.The REM stage takes place throughout the sleep period.REM always follows a period of NREM sleep and accounts for about a quarter of the total sleep period.If you sleep 8 or 9 hours, you'll typically experience REM sleep 4 or 5 times.These sleep stages repeat throughout the sleep period and these repetitions are known as sleep cycles.Several sleep cycles take place during
a single sleep period.As the sleep cycles progress through a sleep period, the amount of REM sleep increases.But as we all
know, there are some nights that getting uninterrupted sleep is much easier than others!Maintain a regular bed and wake time schedule.Establish a regular, relaxing bedtime routine.While England slept, Germany prepared for war.They are sleeping in their tombs.He slept the sleep of the innocent.This trailer sleeps three people.Two friends will sleep over this weekend.Botany The folding together of leaflets or petals at night or in the absence of light.To be in the state of sleep or to fall asleep.To be in a condition resembling sleep.To pass or get rid of by sleeping: slept away the day; went home to sleep off the headache.To provide sleeping accommodations for: This tent sleeps three comfortably.To sleep at one's place of employment: a butler and a chauffeur who sleep in.To oversleep: I missed the morning train because I slept in.To sleep late on purpose: After this week's work, I will sleep in on Saturday.To sleep at one's own home, not at one's place of employment.To sleep away from one's home.To be sexually active with more than one partner.To sleep at one's place of employment: a butler and a chauffeur who sleep in.To oversleep: I missed the morning train because I slept in.To sleep late on purpose: After this week's work, I will sleep in on Saturday.To think about (something) overnight before deciding.To sleep at one's own home, not at one's place of employment.To sleep away from one's home.To spend the night as a guest in another's home.To have sexual relations.To have sexual relations with.To sleep very deeply.Sleep with "do the sex act with" is in O.Sleep around first attested 1928.Sleeping sickness as a specific African tropical disease is first recorded 1875.Sleepless is from 1412; sleepy first attested c.To be able to do something in (one's) sleep "easily" is recorded from 1953.Share This
sleep In addition to the idioms beginning with sleep, also see let sleeping dogs lie; lose sleep over; put to sleep.Also see under asleep.Example: It is bad for you to have too little sleep, since it makes you tired; I had only four hours' sleep last night.During sleep, the eyes usually close, the muscles relax, and responsiveness to external stimuli decreases.REM sleep and the last stage consisting of REM sleep.These stages constitute a sleep cycle that repeats itself about five times during a normal episode of sleep.Stage I is characterized by drowsiness, Stage II by light sleep, and Stages III and IV by deep sleep.Stages II and III repeat themselves before REM sleep (Stage V), which occurs about 90 minutes after the onset of sleep.During REM sleep, dreams occur, and memory is thought to be organized.REM sleep, there are no dreams, and brain activity decreases while the body recovers from wakeful activity.The amount and periodicity of sleep in humans vary with age, with infants sleeping frequently for shorter periods, and mature adults sleeping for longer uninterrupted periods.REM sleep, REM sleep.To be in the state of sleep.Published by Houghton Mifflin Company.Share This
sleep 1.Also used in the phrase "sleep on" (or "block on") some external event, meaning to wait for it.Share This
sleep vi.In jargon, used very similarly to v.They can't get the fix I've been asking for into the next release, so I'm going to sleep on it until the release, then start hassling them again.Share This
Ten Sleep, WY (town, FIPS 75790) Location: 44.Web Search powered by Google
Thesaurus. |
 |
 |
|
|
|
|
|
![Blaze : As Live As It Gets [CD 1]](/covers/46/4669/alb_63873_th.jpg "Blaze : As Live As It Gets [CD 1]")
