Misplaced Pages

#157842

96-525: NPAC may stand for: News Photographers Association of Canada National Pain Advocacy Center Nocturnal post absorptive catabolism Northeast Parallel Architecture Center, Syracuse University North Point Alliance Church, Hong Kong Number Portability Administration Center , telecoms North Pacific accumulation zone North Pacific Arctic Conference Topics referred to by

192-405: A 24-hour cycle, whereas in monophasic sleep this occurs all at once. Under experimental conditions, humans tend to alternate more frequently between sleep and wakefulness (i.e., exhibit more polyphasic sleep) if they have nothing better to do. Given a 14-hour period of darkness in experimental conditions, humans tended towards bimodal sleep, with two sleep periods concentrated at the beginning and at

288-754: A better understanding and offer possibilities to improve targeting of at-risk populations—and the implementation of treatments to curb the cognitive decline of AD patients. In individuals with psychiatric illnesses sleep disorders may include a variety of clinical symptoms, including but not limited to: excessive daytime sleepiness, difficulty falling asleep, difficulty staying asleep, nightmares, sleep talking, sleepwalking, and poor sleep quality. Sleep disturbances - insomnia, hypersomnia and delayed sleep-phase disorder - are quite prevalent in severe mental illnesses such as psychotic disorders. In those with schizophrenia , sleep disorders contribute to cognitive deficits in learning and memory. Sleep disturbances often occur before

384-407: A brain area directly above the optic chiasm , is presently considered the most important nexus for this process; however, secondary clock systems have been found throughout the body. An organism whose circadian clock exhibits a regular rhythm corresponding to outside signals is said to be entrained ; an entrained rhythm persists even if the outside signals suddenly disappear. If an entrained human

480-538: A child's quality of sleep as well as prepare them to make and keep healthy sleep hygiene habits in the future. Children need many hours of sleep per day in order to develop and function properly: up to 18 hours for newborn babies, with a declining rate as a child ages. Early in 2015, after a two-year study, the National Sleep Foundation in the US announced newly revised recommendations as shown in

576-414: A factor which may exacerbate disruption of the circadian cycle. Scientific studies on sleep have shown that sleep stage at awakening is an important factor in amplifying sleep inertia . Determinants of alertness after waking up include quantity/quality of the sleep, physical activity the day prior, a carbohydrate-rich breakfast, and a low blood glucose response to it. Sleep timing is controlled by

672-616: A full eight hours. Researchers have found that sleeping 6–7 hours each night correlates with longevity and cardiac health in humans, though many underlying factors may be involved in the causality behind this relationship. Sleep difficulties are furthermore associated with psychiatric disorders such as depression , alcoholism , and bipolar disorder . Up to 90 percent of adults with depression are found to have sleep difficulties. Dysregulation detected by EEG includes disturbances in sleep continuity, decreased delta sleep and altered REM patterns with regard to latency, distribution across

768-407: A function of the amount of time elapsed since the last adequate sleep episode) 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. The timing is correct when the following two circadian markers occur after the middle of the sleep episode and before awakening: maximum concentration of

864-413: A good night's sleep. The American Academy of Sleep Medicine (AASM) divides NREM into three stages: N1, N2, and N3, the last of which is also called delta sleep or slow-wave sleep . The whole period normally proceeds in the order: N1 → N2 → N3 → N2 → REM. REM sleep occurs as a person returns to stage 2 or 1 from a deep sleep. There is a greater amount of deep sleep (stage N3) earlier in the night, while

960-469: A growing resemblance between some sleep stages (N1 and N2). More than 65% of people with Alzheimer's disease have this type of sleep disturbance. One factor that could explain this change in sleep architecture is a change in circadian rhythm, which regulates sleep. A disruption of the circadian rhythm would generate sleep disturbances. Some studies show that people with AD have a delayed circadian rhythm, whereas in normal aging, an advanced circadian rhythm

1056-462: A hereditary component. A total of 632 participants, half with iRBD and half without, completed self-report questionnaires. The results of the study suggest that people with iRBD are more likely to report having a first-degree relative with the same sleep disorder than people of the same age and sex that do not have the disorder. More research needs to be conducted to further understand the hereditary nature of sleep disorders. A population susceptible to

SECTION 10

#1732786545158

1152-977: A necessary diagnostic criterion—but one of the most frequent symptoms of individuals with major depressive disorder (MDD). Among individuals with MDD, insomnia and hypersomnia have prevalence estimates of 88% and 27%, respectively, whereas individuals with insomnia have a threefold increased risk of developing MDD. Depressed mood and sleep efficiency strongly co-vary, and while sleep regulation problems may precede depressive episodes, such depressive episodes may also precipitate sleep deprivation. Fatigue, as well as sleep disturbances such as irregular and excessive sleepiness, are linked to symptoms of depression. Recent research has even pointed to sleep problems and fatigues as potential driving forces bridging MDD symptoms to those of co-occurring generalized anxiety disorder. Treatments for sleep disorders generally can be grouped into four categories: None of these general approaches are sufficient for all patients with sleep disorders. Rather,

1248-418: A particular frequency corresponds to various points in the sleep-wake cycle, such as being asleep, being awake, or falling asleep. Alpha, beta, theta, gamma, and delta waves are all seen in the different stages of sleep. Each waveform maintains a different frequency and amplitude. Alpha waves are seen when a person is in a resting state, but is still fully conscious. Their eyes may be closed and all of their body

1344-564: A positive feedback relationship. As a result, sleep disturbances are no longer only a symptom of AD; the relationship between sleep disturbances and AD is bidirectional. At the same time, it has been shown that memory consolidation in long-term memory (which depends on the hippocampus) occurs during NREM sleep. This indicates that a decrease in the NREM sleep will result in less consolidation, resulting in poorer memory performances in hippocampal-dependent long-term memory. This drop in performance

1440-445: A screen before bed may interfere with sleep. Modern humans often find themselves desynchronized from their internal circadian clock, due to the requirements of work (especially night shifts ), long-distance travel, and the influence of universal indoor lighting. Even if they have sleep debt, or feel sleepy, people can have difficulty staying asleep at the peak of their circadian cycle. Conversely, they can have difficulty waking up in

1536-438: A structured bedtime routine. This can look differently among families, but will generally consist of a set of rituals such as reading a bedtime story, a bath, brushing teeth, and can also include a show of affection from the parent to the child such a hug or kiss before bed. A bedtime routine will also include a consistent time that the child is expected to be in bed ready for sleep. Having a reliable bedtime routine can help improve

1632-611: A subjective point of view. Objective sleep quality refers to how difficult it is for a person to fall asleep and remain in a sleeping state, and how many times they wake up during a single night. Poor sleep quality disrupts the cycle of transition between the different stages of sleep. Subjective sleep quality in turn refers to a sense of being rested and regenerated after awaking from sleep. A study by A. Harvey et al. (2002) found that insomniacs were more demanding in their evaluations of sleep quality than individuals who had no sleep problems. Homeostatic sleep propensity (the need for sleep as

1728-413: A succession of images, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. During sleep, most of the body's systems are in an anabolic state, helping to restore the immune , nervous , skeletal , and muscular systems; these are vital processes that maintain mood , memory , and cognitive function , and play a large role in the function of

1824-540: A transitional period is called slow-wave sleep or deep sleep. During this phase, body temperature and heart rate fall, and the brain uses less energy. REM sleep, also known as paradoxical sleep, represents a smaller portion of total sleep time. It is the main occasion for dreams (or nightmares ), and is associated with desynchronized and fast brain waves, eye movements, loss of muscle tone, and suspension of homeostasis . The sleep cycle of alternate NREM and REM sleep takes an average of 90 minutes, occurring 4–6 times in

1920-522: Is adenosine , a neurotransmitter that inhibits many of the bodily processes associated with wakefulness. Adenosine levels increase in the cortex and basal forebrain during prolonged wakefulness, and decrease during the sleep-recovery period, potentially acting as a homeostatic regulator of sleep. Coffee , tea, and other sources of caffeine temporarily block the effect of adenosine, prolong sleep latency, and reduce total sleep time and quality. Humans are also influenced by aspects of social time , such as

2016-557: Is accumulated against an individual's average sleep or some other benchmark. It is also unclear whether the prevalence of sleep debt among adults has changed appreciably in the industrialized world in recent decades. Sleep debt does show some evidence of being cumulative. Subjectively, however, humans seem to reach maximum sleepiness 30 hours after waking. It is likely that in Western societies , children are sleeping less than they previously have. One neurochemical indicator of sleep debt

SECTION 20

#1732786545158

2112-527: Is also common among adolescents, whose school schedules are often incompatible with their natural circadian rhythm. Effective treatment begins with careful diagnosis using sleep diaries and perhaps sleep studies. Modifications in sleep hygiene may resolve the problem, but medical treatment is often warranted. Special equipment may be required for treatment of several disorders such as obstructive apnea, circadian rhythm disorders and bruxism. In severe cases, it may be necessary for individuals to accept living with

2208-449: Is different from Wikidata All article disambiguation pages All disambiguation pages Nocturnal post absorptive catabolism Sleep is a state of reduced mental and physical activity in which consciousness is altered and certain sensory activity is inhibited. During sleep, there is a marked decrease in muscle activity and interactions with the surrounding environment. While sleep differs from wakefulness in terms of

2304-663: Is generally studied in adults, rather than children. Further research would be needed to study the effects of acupuncture on sleep disorders in children. Research suggests that hypnosis may be helpful in alleviating some types and manifestations of sleep disorders in some patients. "Acute and chronic insomnia often respond to relaxation and hypnotherapy approaches, along with sleep hygiene instructions." Hypnotherapy has also helped with nightmares and sleep terrors. There are several reports of successful use of hypnotherapy for parasomnias specifically for head and body rocking, bedwetting and sleepwalking. Hypnotherapy has been studied in

2400-449: Is insomnia, in addition to hypersomnia, nightmares, poor sleep quality, OSA, extreme daytime sleepiness, etc. Moreover, animal models have shown that sleep debt can induce episodes of bipolar mania in laboratory mice, but these models are still limited in their potential to explain bipolar disease in humans with all its multifaceted symptoms, including those related to sleep disturbances. Sleep disturbances (insomnia or hypersomnia) are not

2496-399: Is isolated in a bunker with constant light or darkness, he or she will continue to experience rhythmic increases and decreases of body temperature and melatonin, on a period that slightly exceeds 24 hours. Scientists refer to such conditions as free-running of the circadian rhythm. Under natural conditions, light signals regularly adjust this period downward, so that it corresponds better with

2592-450: Is known as a "natural short sleeper". This condition is not to be confused with intentional sleep deprivation, which leaves symptoms such as irritability or temporarily impaired cognitive abilities in people who are predisposed to sleep a normal amount of time but not in people with FNSS. The genes DEC2 , ADRB1 , NPSR1 and GRM1 are implicated in enabling short sleep. The quality of sleep may be evaluated from an objective and

2688-422: Is observed to be a necessary behavior across most of the animal kingdom, including some of the least cognitively advanced animals which have no need for other functions of sleep, such as memory consolidation or dreaming. It has been widely accepted that sleep must support the formation of long-term memory, and generally increasing previous learning and experiences recalls. However, its benefit seems to depend on

2784-835: Is one of the central symptoms of AD. Recent studies have also linked sleep disturbances, neurogenesis and AD. The subgranular zone and the subventricular zone continued to produce new neurons in adult brains. These new cells are then incorporated into neuronal circuits and the subgranular zone, which is found in the hippocampus. These new cells contribute to learning and memory, playing an essential role in hippocampal-dependent memory. However, recent studies have shown that several factors can interrupt neurogenesis, including stress and prolonged sleep deprivation (more than one day). The sleep disturbances encountered in AD could therefore suppress neurogenesis—and thus impair hippocampal functions. This would contribute to diminished memory performances and

2880-414: Is present. In addition to these psychological symptoms, at a neurological level there are two main symptoms of Alzheimer's disease. The first is an accumulation of beta-amyloid waste forming aggregate "plaques". The second is an accumulation of tau protein. It has been shown that the sleep-wake cycle acts on the beta-amyloid burden, which is a central component found in AD. As individuals awaken,

2976-443: Is profoundly influenced by changes in light, since these are its main clues about what time it is. Exposure to even small amounts of light during the night can suppress melatonin secretion, and increase body temperature and wakefulness. Short pulses of light, at the right moment in the circadian cycle, can significantly 'reset' the internal clock. Blue light, in particular, exerts the strongest effect, leading to concerns that use of

NPAC - Misplaced Pages Continue

3072-710: Is recognized by the American Academy of Sleep Medicine (AASM), and these dentists are organized in the Academy of Dental Sleep Medicine (USA). Occupational therapy is an area of medicine that can also address a diagnosis of sleep disorder, as rest and sleep is listed in the Occupational Therapy Practice Framework (OTPF) as its own occupation of daily living. Rest and sleep are described as restorative in order to support engagement in other occupational therapy occupations. In

3168-400: Is regulated by a process called homeostasis . Induced or perceived lack of sleep is called sleep deprivation . Process S is driven by the depletion of glycogen and accumulation of adenosine in the forebrain that disinhibits the ventrolateral preoptic nucleus , allowing for inhibition of the ascending reticular activating system . Sleep deprivation tends to cause slower brain waves in

3264-489: Is responsible for this through the phenomenon of glymphatic clearance. Thus, during wakefulness, the AB burden is greater because the metabolic activity and oxidative stress are higher, and there is no protein degradation by the glymphatic clearance. During sleep, the burden is reduced as there is less metabolic activity and oxidative stress (in addition to the glymphatic clearance that occurs). Glymphatic clearance occurs during

3360-443: Is resting and relatively still, where the body is starting to slow down. Beta waves take over alpha waves when a person is at attention, as they might be completing a task or concentrating on something. Beta waves consist of the highest of frequencies and the lowest of amplitude, and occur when a person is fully alert. Gamma waves are seen when a person is highly focused on a task or using all their concentration. Theta waves occur during

3456-713: Is sometimes absent), spindles and the length of time spent in REM sleep are also reduced, while its latency increases. Poor sleep onset in AD has been associated with dream-related hallucination, increased restlessness, wandering and agitation that seem related to sundowning - a typical chronobiological phenomenon presented in the disease. In Alzheimer's disease, in addition to cognitive decline and memory impairment, there are also significant sleep disturbances with modified sleep architecture. The latter may consist in sleep fragmentation, reduced sleep duration, insomnia, increased daytime napping, decreased quantity of some sleep stages, and

3552-416: Is useful in helping people fall asleep faster (decreased sleep latency ), stay asleep longer, and experience improved sleep quality. To test this, a study was conducted that compared subjects who had taken melatonin to subjects with primary sleep disorders who had taken a placebo. Researchers assessed sleep onset latency, total minutes slept, and overall sleep quality in the melatonin and placebo groups to note

3648-721: The American Board of Sleep Medicine . Those passing the Sleep Medicine Specialty Exam received the designation "diplomate of the ABSM ". Sleep medicine is now a recognized subspecialty within internal medicine , family medicine , pediatrics , otolaryngology , psychiatry and neurology in the United States . Certification in Sleep medicine shows that the specialist: has demonstrated expertise in

3744-488: The circadian clock (Process C), sleep-wake homeostasis (Process S), and to some extent by the individual will. Sleep timing depends greatly on hormonal signals from the circadian clock, or Process C, a complex neurochemical system which uses signals from an organism's environment to recreate an internal day–night rhythm. Process C counteracts the homeostatic drive for sleep during the day (in diurnal animals) and augments it at night. The suprachiasmatic nucleus (SCN),

3840-764: The endocrine and immune systems . The internal circadian clock promotes sleep daily at night , when it is dark. The diverse purposes and mechanisms of sleep are the subject of substantial ongoing research. Sleep is a highly conserved behavior across animal evolution, likely going back hundreds of millions of years. Humans may suffer from various sleep disorders , including dyssomnias , such as insomnia , hypersomnia , narcolepsy , and sleep apnea ; parasomnias , such as sleepwalking and rapid eye movement sleep behavior disorder ; bruxism ; and circadian rhythm sleep disorders . The use of artificial light has substantially altered humanity's sleep patterns. Common sources of artificial light include outdoor lighting and

3936-437: The frontal cortex , shortened attention span, higher anxiety, impaired memory, and a grouchy mood. Conversely, a well-rested organism tends to have improved memory and mood. Neurophysiological and functional imaging studies have demonstrated that frontal regions of the brain are particularly responsive to homeostatic sleep pressure. There is disagreement on how much sleep debt is possible to accumulate, and whether sleep debt

NPAC - Misplaced Pages Continue

4032-456: The 70s and 80s, the medical importance of sleep was recognized. By the 1970s in the US, clinics and laboratories devoted to the study of sleep and sleep disorders had been founded, and a need for standards arose. The medical community began paying more attention to primary sleep disorders, such as sleep apnea, as well as the role and quality of sleep in other conditions. Specialists in sleep medicine were originally and continue to be certified by

4128-463: The NREM SWS sleep. This sleep stage decreases in normal aging, resulting in less glymphatic clearance and increased AB burden that will form AB plaques. Therefore, sleep disturbances in individuals with AD will amplify this phenomenon. The decrease in the quantity and quality of the NREM SWS, as well as the disturbances of sleep will therefore increase the AB plaques. This initially occurs in

4224-860: The OTPF, the occupation of rest and sleep is broken down into rest, sleep preparation, and sleep participation. Occupational therapists have been shown to help improve restorative sleep through the use of assistive devices/equipment, cognitive behavioral therapy for Insomnia , therapeutic activities, and lifestyle interventions. In the UK, knowledge of sleep medicine and possibilities for diagnosis and treatment seem to lag. The Imperial College Healthcare shows attention to obstructive sleep apnea syndrome (OSA) and very few other sleep disorders. Some NHS trusts have specialist clinics for respiratory and neurological sleep medicine. According to one meta-analysis of sleep disorders in children, confusional arousals and sleepwalking are

4320-463: The PD population), hypersomnia (more than 50% of the PD population), and REM sleep behavior disorder (RBD) - that may affect around 40% of the PD population and it is associated with increased motor symptoms. Furthermore, RBD has been highlighted as a strong precursor for future development of those neurodegenerative diseases over several years in prior, which seems to be a great opportunity for improving

4416-422: The ability to react to stimuli , it still involves active brain patterns, making it more reactive than a coma or disorders of consciousness . Sleep occurs in repeating periods , during which the body alternates between two distinct modes: REM and non-REM sleep . Although REM stands for "rapid eye movement", this mode of sleep has many other aspects, including virtual paralysis of the body. Dreams are

4512-447: The absence of volitional sleep deprivation , "is almost inevitably caused by an identifiable and treatable sleep disorder", such as sleep apnea, narcolepsy , idiopathic hypersomnia , Kleine–Levin syndrome , menstrual-related hypersomnia, idiopathic recurrent stupor, or circadian rhythm disturbances . Another common complaint is insomnia, a set of symptoms which can have a great many different causes, physical and mental. Management in

4608-415: The brain and body, the reduced rate of metabolism enables countervailing restorative processes. The brain requires sleep for restoration, whereas these processes can take place during quiescent waking in the rest of the body. The essential function of sleep may be its restorative effect on the brain: "Sleep is of the brain, by the brain and for the brain." This theory is strengthened by the fact that sleep

4704-560: The brain restores its supply of adenosine triphosphate (ATP), the molecule used for short-term storage and transport of energy. In quiet waking, the brain is responsible for 20% of the body's energy use, thus this reduction has a noticeable effect on overall energy consumption. Sleep increases the sensory threshold . In other words, sleeping persons perceive fewer stimuli, but can generally still respond to loud noises and other salient sensory events. During slow-wave sleep , humans secrete bursts of growth hormone . All sleep, even during

4800-443: 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. Often, behavioral/psychotherapeutic and pharmacological approaches may be compatible, and can effectively be combined to maximize therapeutic benefits. Management of sleep disturbances that are secondary to mental, medical, or substance abuse disorders should focus on

4896-654: The day, is associated with the secretion of prolactin . Key physiological methods for monitoring and measuring changes during sleep include electroencephalography (EEG) of brain waves , electrooculography (EOG) of eye movements, and electromyography (EMG) of skeletal muscle activity. Simultaneous collection of these measurements is called polysomnography , and can be performed in a specialized sleep laboratory . Sleep researchers also use simplified electrocardiography (EKG) for cardiac activity and actigraphy for motor movements. The electrical activity seen on an EEG represents brain waves. The amplitude of EEG waves at

SECTION 50

#1732786545158

4992-926: The deepest period of sleep. Napping too long and entering the slow wave cycles can make it difficult to awake from the nap and leave one feeling unrested. This period of drowsiness is called sleep inertia . The siesta habit has recently been associated with a 37% lower coronary mortality, possibly due to reduced cardiovascular stress mediated by daytime sleep. Short naps at mid-day and mild evening exercise were found to be effective for improved sleep, cognitive tasks, and mental health in elderly people. Monozygotic (identical) but not dizygotic (fraternal) twins tend to have similar sleep habits. Neurotransmitters, molecules whose production can be traced to specific genes, are one genetic influence on sleep that can be analyzed. The circadian clock has its own set of genes. Genes which may influence sleep include ABCC9 , DEC2 , Dopamine receptor D2 and variants near PAX 8 and VRK2 . While

5088-505: The degree of impairment is related to the severity of those symptoms. Treatment of allergies has also been shown to help sleep apnea. A review of the evidence in 2012 concluded that current research is not rigorous enough to make recommendations around the use of acupuncture for insomnia . The pooled results of two trials on acupuncture showed a moderate likelihood that there may be some improvement to sleep quality for individuals with insomnia. This form of treatment for sleep disorders

5184-824: The development of sleep disorders includes people who have experienced a traumatic brain injury (TBI) . Because many researchers have focused on this issue, a systematic review was conducted to synthesize their findings. The results indicate that individuals who experienced a TBI are most disproportionately at risk for developing narcolepsy, obstructive sleep apnea, excessive daytime sleepiness, and insomnia. Neurodegenerative diseases have often been associated with sleep disorders, mainly when they are characterized by abnormal accumulation of alpha-synuclein , such as multiple system atrophy (MSA), Parkinson's disease (PD) and Lewy body disease (LBD). For instance, people diagnosed with PD have often presented different kinds of sleep concerns, commonly in regard to insomnia (around 70% of

5280-520: The diagnosis and management of clinical conditions that occur during sleep, that disturb sleep, or that are affected by disturbances in the wake-sleep cycle. This specialist is skilled in the analysis and interpretation of comprehensive polysomnography, and well-versed in emerging research and management of a sleep laboratory. Competence in sleep medicine requires an understanding of a myriad of very diverse disorders. Many of which present with similar symptoms such as excessive daytime sleepiness, which, in

5376-399: The differences. In the end, researchers found that melatonin decreased sleep onset latency and increased total sleep time but had an insignificant and inconclusive impact on the quality of sleep compared to the placebo group. Due to rapidly increasing knowledge and understanding of sleep in the 20th century, including the discovery of REM sleep in the 1950s and circadian rhythm disorders in

5472-413: The disorder, however well managed. Some sleep disorders have been found to compromise glucose metabolism. Histamine plays a role in wakefulness in the brain. An allergic reaction over produces histamine, causing wakefulness and inhibiting sleep. Sleep problems are common in people with allergic rhinitis . A study from the N.I.H. found that sleep is dramatically impaired by allergic symptoms, and that

5568-568: The elderly, the risk of developing sleep disordered breathing, periodic limb movements, restless legs syndrome , REM sleep behavior disorders, insomnia, and circadian rhythm disturbances is especially increased. A systematic review found that traumatic childhood experiences (such as family conflict or sexual trauma) significantly increases the risk for a number of sleep disorders in adulthood, including sleep apnea , narcolepsy , and insomnia . In addition, an evidence-based synopsis suggests that idiopathic REM sleep behavior disorder (iRBD) may have

5664-514: The end of the dark time. Bimodal sleep in humans was more common before the Industrial Revolution . Different characteristic sleep patterns, such as the familiarly so-called " early bird " and " night owl ", are called chronotypes . Genetics and sex have some influence on chronotype, but so do habits. Chronotype is also liable to change over the course of a person's lifetime. Seven-year-olds are better disposed to wake up early in

5760-558: The end of the sleep cycle. Awakening involves heightened electrical activation in the brain, beginning with the thalamus and spreading throughout the cortex . On a typical night of sleep, there is not much time that is spent in the waking state. In various sleep studies that have been conducted using the electroencephalography, it has been found that females are awake for 0-1% during their nightly sleep while males are awake for 0-2% during that time. In adults, wakefulness increases, especially in later cycles. One study found 3% awake time in

5856-486: The exact 24 hours of an Earth day. The circadian clock exerts constant influence on the body, affecting sinusoidal oscillation of body temperature between roughly 36.2 °C and 37.2 °C. The suprachiasmatic nucleus itself shows conspicuous oscillation activity, which intensifies during subjective day (i.e., the part of the rhythm corresponding with daytime, whether accurately or not) and drops to almost nothing during subjective night. The circadian pacemaker in

SECTION 60

#1732786545158

5952-533: The first ninety-minute sleep cycle, 8% in the second, 10% in the third, 12% in the fourth, and 13–14% in the fifth. Most of this awake time occurred shortly after REM sleep. Today, many humans wake up with an alarm clock ; however, people can also reliably wake themselves up at a specific time with no need for an alarm. Many sleep quite differently on workdays versus days off, a pattern which can lead to chronic circadian desynchronization. Many people regularly look at television and other screens before going to bed,

6048-431: The first part of an individual's sleep cycle, the first slow wave of sleep During the first slow wave of sleep period of the sleep cycle the mind and body slow down causing one to feel drowsy and relaxed. At this stage it is the easiest to wake up, therefore many children do not remember what happened during this time. Nightmares are also considered a parasomnia among children, who typically remember what took place during

6144-813: The form of overall time asleep, was observed. In order to assess sleep quality, researchers used subjective measures (i.e. questionnaires ) and objective measures (i.e. polysomnography ). The results of the study suggest that music therapy did improve sleep quality in subjects with acute or chronic sleep disorders, though only when tested subjectively. Although these results are not fully conclusive and more research should be conducted, it still provides evidence that music therapy can be an effective treatment for sleep disorders. In another study specifically looking to help people with insomnia, similar results were seen. The participants that listened to music experienced better sleep quality than those who did not listen to music. Listening to slower pace music before bed can help decrease

6240-445: The heart rate, making it easier to transition into sleep. Studies have indicated that music helps induce a state of relaxation that shifts an individual's internal clock towards the sleep cycle. This is said to have an effect on children and adults with various cases of sleep disorders. Music is most effective before bed once the brain has been conditioned to it, helping to achieve sleep much faster. Research suggests that melatonin

6336-412: The highest rate of sleep. The hours that children spend asleep influence their ability to perform on cognitive tasks. Children who sleep through the night and have few night waking episodes have higher cognitive attainments and easier temperaments than other children. Sleep also influences language development. To test this, researchers taught infants a faux language and observed their recollection of

6432-408: The hippocampus, which is a brain structure integral in long-term memory formation. Hippocampus cell death occurs, which contributes to diminished memory performance and cognitive decline found in AD. Although the causal relationship is unclear, the development of AD correlates with the development of prominent sleep disorders. In the same way, sleep disorders exacerbate disease progression, forming

6528-448: The hormone melatonin, and minimum core body temperature. Human sleep-needs vary by age and amongst individuals; sleep is considered to be adequate when there is no daytime sleepiness or dysfunction. Moreover, self-reported sleep duration is only moderately correlated with actual sleep time as measured by actigraphy , and those affected with sleep state misperception may typically report having slept only four hours despite having slept

6624-475: The hours when other people are awake, the hours when work is required, the time on clocks, etc. Time zones , standard times used to unify the timing for people in the same area, correspond only approximately to the natural rising and setting of the sun. An extreme example of the approximate nature of time zones is China, a country which used to span five time zones and now officially uses only one (UTC+8). In polyphasic sleep , an organism sleeps several times in

6720-836: The increasing life expectancy calls for a deeper understanding of the relationship between sleep disorders and neurodegenerative disease. Sleep disturbances have been also observed in Alzheimer's disease (AD), affecting about 45% of its population. When based on caregiver reports, this percentage increases to about 70%. As well as in PD population, insomnia and hypersomnia are frequently recognized in AD patients, which have been associated with accumulation of beta-amyloid , circadian rhythm sleep disorders (CRSD) and melatonin alteration. Additionally, changes in sleep architecture are observed in AD. Although sleep architecture seems to naturally change with age, its development appears aggravated in AD patients. SWS potentially decreases (and

6816-489: The latter have been found in a GWAS study that primarily detects correlations (but not necessarily causation), other genes have been shown to have a more direct effect. For instance, mice lacking dihydropyrimidine dehydrogenase (Dpyd) had 78.4 min less sleep during the lights-off period than wild-type mice. Dpyd encodes the rate-limiting enzyme in the metabolic pathway that catabolizes uracil and thymidine to β- alanine , an inhibitory neurotransmitter . This also supports

6912-485: The main behavioral symptoms of bipolar disorder is abnormal sleep. Studies have suggested that 23-78% of individuals with bipolar disorders consistently report symptoms of excessive time spent sleeping, or hypersomnia. The pathogenesis of bipolar disorder, including the higher risk of suicidal ideation, could possibly be linked to circadian rhythm variability, and sleep disturbances are a good predictor of mood swings. The most common sleep-related symptom of bipolar disorder

7008-422: The middle of the night. Circadian rhythm exerts some influence on the nighttime secretion of growth hormone. The circadian rhythm influences the ideal timing of a restorative sleep episode. Sleepiness increases during the night. REM sleep occurs more during body temperature minimum within the circadian cycle, whereas slow-wave sleep can occur more independently of circadian time. The internal circadian clock

7104-496: The morning than are fifteen-year-olds. Chronotypes far outside the normal range are called circadian rhythm sleep disorders. Naps are short periods of sleep that one might take during the daytime, often in order to get the necessary amount of rest. Napping is often associated with childhood, but around one-third of American adults partake in it daily. The optimal nap duration is around 10–20 minutes, as researchers have proven that it takes at least 30 minutes to enter slow-wave sleep,

7200-405: The night and density of eye movements. Sleep duration can also vary according to season. Up to 90% of people report longer sleep duration in winter, which may lead to more pronounced seasonal affective disorder . By the time infants reach the age of two, their brain size has reached 90 percent of an adult-sized brain; a majority of this brain growth has occurred during the period of life with

7296-540: The onset of psychosis. Sleep deprivation can also produce hallucinations, delusions and depression. A 2019 study investigated the three above-mentioned sleep disturbances in schizophrenia-spectrum (SCZ) and bipolar (BP) disorders in 617 SCZ individuals, 440 BP individuals, and 173 healthy controls (HC). Sleep disturbances were identified using the Inventory for Depressive Symptoms - clinician rated scale (IDS-C). Results suggested that at least one type of sleep disturbance

7392-466: The period of a person being awake, and they continue to transition into Stage 1 of sleep and in stage 2. Delta waves are seen in stages 3 and 4 of sleep when a person is in their deepest of sleep. Sleep is divided into two broad types: non-rapid eye movement (non-REM or NREM) sleep and rapid eye movement (REM) sleep. Non-REM and REM sleep are so different that physiologists identify them as distinct behavioral states. Non-REM sleep occurs first and after

7488-508: The phase of sleep and the type of memory. For example, declarative and procedural memory-recall tasks applied over early and late nocturnal sleep, as well as wakefulness controlled conditions, have been shown that declarative memory improves more during early sleep (dominated by SWS) while procedural memory during late sleep (dominated by REM sleep) does so. Sleep disorder Sleep disorders are broadly classified into dyssomnias , parasomnias , circadian rhythm sleep disorders involving

7584-499: The production of beta-amyloid protein will be more consistent than its production during sleep. This is explained by two phenomena. The first is that the metabolic activity will be higher during waking, thus resulting in greater secretion of beta-amyloid protein. The second is that oxidative stress will also increase, which leads to greater AB production. On the other hand, it is during sleep that beta-amyloid residues are degraded to prevent plaque formation. The glymphatic system

7680-443: The progression of AD, and the progression of AD would aggravate sleep disturbances. Changes in sleep architecture found in patients with AD occur during the preclinical phase of AD. These changes could be used to detect those most at risk of developing AD. However, this is still only theoretical. While the exact mechanisms and the causal relationship between sleep disturbances and AD remains unclear, these findings already provide

7776-451: The proportion of REM sleep increases in the two cycles just before natural awakening. Awakening can mean the end of sleep, or simply a moment to survey the environment and readjust body position before falling back asleep. Sleepers typically awaken soon after the end of a REM phase or sometimes in the middle of REM. Internal circadian indicators , along with a successful reduction of homeostatic sleep need, typically bring about awakening and

7872-435: The role of β-alanine as a neurotransmitter that promotes sleep in mice. Familial natural short sleep is a rare, genetic, typically inherited trait where an individual sleeps for fewer hours than average without suffering from daytime sleepiness or other consequences of sleep deprivation . This process is entirely natural in this kind of individual, and it is caused by certain genetic mutations. A person with this trait

7968-400: The rules for that language. Infants who slept within four hours of learning the language could remember the language rules better, while infants who stayed awake longer did not recall those rules as well. There is also a relationship between infants' vocabulary and sleeping: infants who sleep longer at night at 12 months have better vocabularies at 26 months. Children can greatly benefit from

8064-405: The same term [REDACTED] This disambiguation page lists articles associated with the title NPAC . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=NPAC&oldid=1246985658 " Category : Disambiguation pages Hidden categories: Short description

8160-471: The screens of electronic devices such as smartphones and televisions, which emit large amounts of blue light, a form of light typically associated with daytime. This disrupts the release of the hormone melatonin needed to regulate the sleep cycle . The most pronounced physiological changes in sleep occur in the brain. The brain uses significantly less energy during sleep than it does when awake, especially during non-REM sleep. In areas with reduced activity,

8256-400: The suprachiasmatic nucleus has a direct neural connection to the pineal gland , which releases the hormone melatonin at night. Cortisol levels typically rise throughout the night, peak in the awakening hours , and diminish during the day. Circadian prolactin secretion begins in the late afternoon, especially in women, and is subsequently augmented by sleep-induced secretion, to peak in

8352-561: The table below. Sleep may facilitate the synthesis of molecules that help repair and protect the brain from metabolic end products generated during waking. Anabolic hormones, such as growth hormones , are secreted preferentially during sleep. The brain concentration of glycogen increases during sleep, and is depleted through metabolism during wakefulness. The human organism physically restores itself during sleep, occurring mostly during slow-wave sleep during which body temperature, heart rate, and brain oxygen consumption decrease. In both

8448-694: The timing of sleep, and other disorders including ones caused by medical or psychological conditions. When a person struggles to fall asleep or stay asleep with no obvious cause , it is referred to as insomnia , which is the most common sleep disorder. Others include sleep apnea , narcolepsy and hypersomnia (excessive sleepiness at inappropriate times), sleeping sickness (disruption of sleep cycle due to infection), sleepwalking , and night terrors . Sleep disruptions can be caused by various issues, including teeth grinding ( bruxism ) and night terrors. Management of sleep disturbances that are secondary to mental, medical or substance abuse disorders should focus on

8544-448: The treatment of sleep disorders in both adults and children. Although more research should be done to increase the reliability of this method of treatment, research suggests that music therapy can improve sleep quality in acute and chronic sleep disorders. In one particular study, participants (18 years or older) who had experienced acute or chronic sleep disorders were put in a randomly controlled trial, and their sleep efficiency, in

8640-534: The treatments of the disease. The neurodegenerative conditions are commonly related to structural brain impairment, which might disrupt the states of sleep and wakefulness, circadian rhythm, motor or non motor functioning. On the other hand, sleep disturbances are frequently related to worsening patient's cognitive functioning, emotional state and quality of life. Furthermore, these abnormal behavioral symptoms negatively contribute to overwhelming their relatives and caregivers. The limited research related to it and

8736-421: The trough of the cycle. A healthy young adult entrained to the sun will (during most of the year) fall asleep a few hours after sunset, experience body temperature minimum at 6 a.m., and wake up a few hours after sunrise. Generally speaking, the longer an organism is awake, the more it feels a need to sleep ("sleep debt"). This driver of sleep is referred to as Process S . The balance between sleeping and waking

8832-462: The two most common sleep disorders among children. An estimated 17.3% of kids between 3 and 13 years old experience confusional arousals. About 17% of children sleepwalk, with the disorder being more common among boys than girls, the peak ages of sleepwalking are from 8 to 12 years old. A different systematic review offers a high range of prevalence rates of sleep bruxism for children. Parasomnias like sleepwalking and talking typically occur during

8928-457: The underlying conditions. Primary sleep disorders are common in both children and adults. However, there is a significant lack of awareness of children with sleep disorders, due to most cases being unidentified. Several common factors involved in the onset of a sleep disorder include increased medication use, age-related changes in circadian rhythms, environmental changes, lifestyle changes, pre-diagnosed physiological problems, or stress. Among

9024-524: The underlying conditions. Medications and somatic treatments may provide the most rapid symptomatic relief from certain disorders, such as narcolepsy, which is best treated with prescription drugs such as modafinil . Others, such as chronic and primary insomnia, may be more amenable to behavioral interventions—with more durable results. Chronic sleep disorders in childhood, which affect some 70% of children with developmental or psychological disorders, are under-reported and under-treated. Sleep-phase disruption

9120-605: The varying situations differs greatly and cannot be undertaken without a correct diagnosis. Sleep dentistry ( bruxism , snoring and sleep apnea ), while not recognized as one of the nine dental specialties , qualifies for board-certification by the American Board of Dental Sleep Medicine (ABDSM). The qualified dentists collaborate with sleep physicians at accredited sleep centers, and can provide oral appliance therapy and upper airway surgery to treat or manage sleep-related breathing disorders. The resulting diplomate status

9216-569: Was reported in 78% of the SCZ population, in 69% individuals with BD, and in 39% of healthy controls. The SCZ group reported the most number of sleep disturbances compared to the BD and HC groups; specifically, hypersomnia was more frequent among individuals with SCZ, and delayed sleep phase disorder was three times more common in the SCZ group compared to the BD group. Insomnias were the most frequently reported sleep disturbance across all three groups. One of

#157842