1. What is sleep?
Even though sleep is characterized by very low physical activity and almost no awareness of the environment, it is still an active, highly organized sequence of events and physiological states. Sleep consists of two clearly distinguishable states: non-REM sleep (non rapid eye movement sleep), i.e. a sleep phase without rapid eye movements, and REM sleep (rapid eye movement sleep), the phase characterized by rapid eye movements. Dreams occur mainly in REM sleep, but sometimes dream content is also described after waking from non-REM sleep. Non-REM sleep is further divided into stages N1, N2 and N3, which differ in terms of amplitude and speed of brain waves produced by the sleeper. Stage N 3 of non-REM sleep is characterized by the largest and slowest brain waves and is therefore summarized in the term ,,slow wave sleep". It has been found that a sleeper is hardest to wake up from this stage of sleep phases, so it is also called ,,deep sleep". Especially in this stage of non-REM sleep, growth hormone is released from the pituitary gland, the so-called. pituitary gland, secretes. This is the basis for the assumption that during sleep the body regenerates from the tiring activities of the waking state. During the REM phase, sleepers react very differently to wake-up stimuli: sometimes the slightest noise is enough to wake them up, other times much stronger stimuli are needed. This fact suggests that a phase of deep sleep also occurs during REM sleep. During REM sleep, one can observe the sleeper's eyes moving under closed eyelids. With the exception of the diaphragm and eye muscles, the welcoming culture is paralyzed and temperature regulation is partially suspended.
2. Why do we sleep?
Sleep is necessary for the functioning of the brain and the survival of the entire organism. It is now believed that sleep has a number of functions. The importance of sleep becomes clear from the consequences of sleep deprivation. These include disruption of cognitive functions and weight gain. Prolonged sleep deprivation can lead to cell damage. On the one hand, sleep serves to save energy. During sleep, a person can fast for a fairly long period of time. There are close links between sleep and metabolism. Likewise, an important role of sleep in memory formation is well documented. A night spent asleep, but also a short sleep, a "nap" during the day, led to the fact that previously learned knowledge and also previously acquired motor skills are better mastered in the waking state than without sleep. Feeling tired is only one of several factors for sleep readiness. Variations in the time of day also play a role. It is well established that every living thing has a circadian (i.e., approximately 24-hour) periodicity of activity and rest phases. The timing and control of this sleep-wake cycle depend on one or more biological clocks in our bodies. These internal clocks are sensitive to light and over time have become approximately synchronized with the 24-hour light-dark cycle of the external environment. Sleep thus appears as an indispensable part of behavior. Humans are physiologically programmed to sleep every day.
3. How much sleep do we need?
There is no generally valid "normal" sleeping measurement. The average sleep duration for adults is 7-8 hours. However, there are people who feel well rested after only 5 hours, while others need more than 10 hours to be rested during the day. Your optimal sleeping measure is exhausted when they can concentrate on an activity during the day without getting sleepy, even if they are sitting down for long periods of time. We cannot force ourselves to considerably exceed or fall below our sleep optimum over a longer period of time. One hour less sleep than usual, for several nights, leads to a feeling of tiredness and fatigue during the day. On the other hand, exceeding our optimal sleep duration for an extended period of time causes poorer sleep with frequent awakenings, especially in the morning hours. Scientists assume that the optimal amount of sleep required in each case varies biologically from person to person. Our individual sleep requirements are determined to a large extent by hereditary factors.
4. Do you need less sleep as you get older?
Recent studies show that healthy older people sleep as much as they did as young adults. The widespread assumption of lower sleep requirements in the elderly is likely due to the fact that physical impairments such as pain often interfere with healthy sleep in old age. For this reason, most elderly people have a so-called polyphonic sleep pattern, with only "light", sometimes interrupted, sleep at night, with additional short sleep episodes during the day.
5. Can missed sleep be made up?
To some extent, you can make up for missed sleep. After major sleep loss, there may be a shift in favor of deep sleep during subsequent nights, although sleep is rarely more than 2-4 hours longer than usual. This is related to the sleep-wake rhythm, which is shaped by our need for sleep and our internal clock.
6. What can you do yourself for a healthy and restful sleep?
The following recommendations may be useful:
- Stick to regular, individualized bedtime and rise times.
- Be consistent regarding naps: either sleep every afternoon or not at all. With occasional afternoon naps, you generally have trouble getting a good night's sleep.
- Get your circulation going regularly in the morning or early afternoon, but avoid strenuous physical activity just before bedtime.
- Avoid rich and hard-to-digest meals before bedtime.
- Use stimulants in moderation and avoid drinking alcohol after dinner. A nightcap disrupts the flow of sleep more than it promotes it and may be responsible for premature morning awakenings.
- Find out for yourself the right room temperature and make sure that it remains constant at night.
- Be careful when handling sleeping pills. Such medications should only be taken on a doctor's order and for short periods of time. Prolonged use can lead to increased insomnia or even addiction.
- Wind down for the day and try to relax before you go to bed. Take a warm bath, read a good book, listen to music and try to avoid mentally stressful situations. And very important: do not think too much about sleep.
- Do not use the bed for eating, watching TV or working. The bed should be there only for sleep and sex.
7. How common are sleep disorders?
Most people complain of sleep onset and sleep through disorders from time to time. About 20 to 30 % of the population report frequent but short-lasting sleep disturbances caused by problems such as family crises, death of a loved one, or job loss. This contrasts with about 4 % of the population who suffer from permanent sleep disturbances that can also lead to impaired daytime performance.
8. What are the causes of sleep disorders?
Today, one speaks of disorders of the sleep-wake behavior. More than 90 different disorders with different causes are distinguished here. Pay for this:
- Sleep onset and sleep maintenance disorders, for example due to situational stresses
- Pronounced sleep disturbances, especially early morning awakenings, as symptoms of major depression
- Nocturnal respiratory disorders (e.g. B. Sleep apnea syndrome)
- Pronounced daytime sleepiness (e.g. B. due to narcolepsy).
- Abnormal sensations and urge to move with periodic movements of the legs at night (restless legs syndrome)
- Unusual nocturnal behaviors, called parasomnias (e.g. B. Sleepwalking, self- and/or other-injurious behavior during sleep, epileptic seizures during sleep).
- Sleep disturbances due to overdose of medication or alcohol
- Sleep disturbances as a result of pain states
- 9. What is the best way to treat sleep disorders?
- Once a specific diagnosis has been made, treatment is aimed at addressing the cause. For example, if excessive consumption of alcohol is the cause of sleep disorders, its reduction must be made. Severe breathing disorders during sleep can be effectively treated with a breathing mask (CPAP therapy). Restless legs syndrome usually responds very well to specific drug treatment.
- Classic sleep medications are best reserved for patients who have developed reactive severe insomnia. These medications should not be taken for longer than four weeks and preferably not every night, and should be supplemented or supplemented by other sleep-restorative measures. then also be replaced.
- A consistent sleep-wake pattern, regular exercise after getting up and abstaining from foods containing caffeine have a supporting effect. Physical activity is helpful when regular exercise is done. However, irregular exercise disrupts rather than challenges sleep the following night. Regular daily exercise, preferably in the morning, truncates an even sleep-wake rhythm and increases the likelihood of sleeping well.
10. What are the signs of sleep apnea syndrome?
Common symptoms include loud, irregular snoring, pauses in breathing reported by the bed partner, profuse night sweats, morning headaches, and marked fatigue and concentration disorders. The cause of apnea is an obstruction of the airways during respiration. The patient struggles to breathe, the effort opens the airways a little so that some air can flow in again. This causes a sudden snoring sound that is very loud after the pause in breathing. This process may be repeated very frequently during the night, each time briefly interrupting sleep, which contributes to pronounced fatigue during the day. In the case of pre-existing heart disease or. of a reduced oxygen content of the blood, sleep apnea can have dangerous consequences.
If sleep apnea causes unpredictable sleep attacks during the day, this can lead to life-threatening situations (microsleep at the wheel). Sleep-related breathing disorders are often associated with obesity and high blood pressure and lead to cardiovascular diseases in the long term. Early diagnosis and treatment is therefore helpful in preventing these diseases.
11. How does "snoring" develop and does it need to be treated?
Snoring is a sound produced by air flowing past irregularities and constrictions in the pharynx and air tubes. It can occur both during inhalation and exhalation. Snoring is usually harmless and in most cases there is no indication for treatment, except when snoring is accompanied by frequent waking reactions (so-called. Arousals), airway constriction, and increased daytime fatigue. In this case, it is also called "obstructive snoring". Snoring can also be the first step in the development of sleep apnea. Weight gain, the use of sleeping pills or alcohol, and anything that causes further constriction or. The obstruction of the mouth and throat can lead to sleep apnea syndrome requiring treatment.
12. What is narcolepsy?
Narcolepsy is a congenital or genetic disorder associated with a chemical imbalance in the area of sleep-wake regulation in the brain. For this reason, the patient suffers sudden sleep attacks during the day. This can take place at any time and anywhere, for example. e.g. during a conversation, while eating, on the street, etc. The appearance of narcolepsy also includes the components of REM sleep, such as paralysis of voluntary muscles and hallucinations, which may occur involuntarily and at a completely abnormal time. Narcoleptic paralysis, also known as cataplexy, is characterized by sudden muscle weakness leading to a "softening" of the knees to a complete collapse, especially as a result of affective stress. After sleep apnea, narcolepsy is the second most frequent cause of pronounced daytime sleepiness and is not uncommon in humans.
With an incidence of about 1:2000, it ranks nearly equal to multiple sclerosis. Men and women are affected with approximately equal frequency. It is currently assumed that environmental factors mediate a reduction or loss of orexin-containing neurons in the brain. It is possible that an autoimmune event plays a central role in this. Orexin is produced by a small group of neurons in the hypothalamus. These cells have an influence on many areas of the brain. Orexin levels can be determined in the cerebrospinal fluid.Narcolepsy is a chronic disorder that can be treated with medication.
13. What does it mean if you can't move for a short time at the moment you fall asleep or wake up?
This phenomenon is called ,,sleep paralysis" and occurs sporadically and without other serious disorders in up to 30% of adults. Some patients report the unpleasant experience of falling and a "fearful awakening" associated with a subjective feeling of paralysis. Scientists assume that this paralytic state is equivalent to an incompletely triggered REM phase, which mainly involves the paralysis of the muscles. Those affected are sometimes completely overwhelmed by the feeling of fear, even if they know that this state of being "paralyzed" only lasts for a short time and is harmless. In pronounced cases, medications are used to suppress REM sleep (e.g.. B. certain antidepressants).
14. What can be done against movements, especially of the legs, during sleep?
Nocturnal twitching, nocturnal myoclonus, or periodic leg movements during sleep are common problems. Most people are not aware of these twitches and do not wake up during them, while for others the movements disturb sleep. Many sufferers do not notice this problem and may complain of insomnia or fatigue during the day. If the leg movements caused sleep disturbances, a specialized center should be visited. However, if the person's sleep is not disturbed by these twitches, then the bed partner must learn not to let it interfere with their sleep. There is another form of sleep disorder known as REM sleep behavior disorder. However, the movements that occur are different from the periodic leg or arm movements. In this disorder, arm, leg, or head movements may occur that are very violent and are most common during the last hours of the night when a lot of REM sleep occurs. These states, often associated with speech, are caused by changes in the brain that normally initiate muscular paralysis in REM sleep. In patients with this disorder, muscle tension is maintained so that dreams are actively acted out. Severe nocturnal leg movements and REM sleep behavior disorder can usually be effectively treated with specific medications.
15. What is restless legs syndrome?
This phenomenon is also called ,,restless legs syndrome" and is relatively common, especially in iron deficiency, pregnancy and kidney dysfunction. Women are affected more frequently than men, but the reason for this is not yet clear. Patients describe - usually only when asked specifically - typically hard-to-describe sensations (tingling, pulling, rumbling, but also pain) mostly in the lower legs, an urge to move when at rest (i.e. lying or sitting), a clear improvement through movement, and an increase in symptoms in the evening or in the evening. during the night. Sleep disturbances are therefore a very frequent consequence of this disease; in severe cases, psychological impairments such as depressive moods may also occur. Sleep is often disturbed by simultaneous periodic leg movements Cause of this neurological disorder has not been fully elucidated, but genetic factors appear to play a significant role. Again and again, family trees with a large number of affected persons are described. If the symptoms are very pronounced, a specific drug treatment can bring about a significant improvement. However, if the symptoms are not very severe or occur only occasionally, medication may not be necessary. It is important to have a previous examination with regard to iron metabolism. In the case of iron deficiency, improvement can be achieved by taking an iron supplement.
16. What can cause a headache in the morning?
There can be many causes for morning headaches, among the most important being nocturnal respiratory disorders or sleep-related vascular changes in the brain. In people with breathing disorders during sleep, the blood is not sufficiently oxygenated, so awakening may be accompanied by headaches and a feeling of fatigue. Nocturnal vascular headaches are caused by spasms of small brain vessels that most often occur during REM sleep. Both forms can be treated well.
17. How does sleepwalking occur?
Sleepwalking, also known as somnambulism, is a state of altered consciousness in which phenomena of sleep and wakefulness occur simultaneously. Sleepwalkers behave as if they were awake. However, the brain waves show that the affected person is in deep sleep. Sleepwalking often begins with a sudden sitting up in bed. The affected persons look around and make a confused impression. Either they then lie down again and go back to sleep, or they get up, get out of bed, and perform seemingly meaningful, thoroughly complex actions. For example, patients are able to converse with another person - seemingly reasonably - or prepare food for themselves. However, because they are not consciously aware of their surroundings, sleepwalkers can put themselves at considerable risk of injury: For example, they may leave their home at night and walk into the street or mistake a door for a window. In exceptional cases, sleepwalkers also behave irritably and aggressively. Most sleepwalking episodes last only a few seconds to a few minutes, rarely much longer. The next morning, there is usually no memory of the events. Sleepwalking occurs most frequently between the 4th and 8th day of life. The first sleepwalking episodes occur at the age of 15 (about 15-20 % of all children sleepwalk once) and much less frequently in adulthood. The reason for the frequent occurrence in childhood is assumed to be a not yet completed maturation of the brain. As a rule, the episodes disappear with the onset of puberty. Drawing lots can include fever, sleep deprivation, and emotional stress factors.
In adulthood, certain medications or nighttime breathing pauses can also trigger episodes of sleepwalking. In most cases, no drug treatment is necessary. The focus is on measures for the safety of the person concerned (e. g. e.g. secure windows and doors), a quiet escort back to the bed or Avoiding potential draws such as sleep deprivation or irregular sleep schedules. However, if it comes to actions endangering oneself or others, specific drug treatment is recommended. Sleepwalking often occurs together with Pavor nocturnus. Pavor nocturnus, also known as ,,sleep terror," is characterized by a sudden awakening from deep sleep with a shrill cry and signs of intense fear. In this state, the affected person does not respond to encouragement, and the excitement usually subsides by itself after a few minutes. In this case, too, the person affected is usually unaware of the nocturnal event the next morning. Sleepwalking and Pavor nocturnus, as well as teeth grinding, head banging, certain forms of wetting oneself and thrashing about during sleep, belong to the group of parasomnias. These sleep disorders should be investigated in a sleep laboratory if there is a risk of injury to self or bed partner or if epileptic seizures during sleep are suspected as a differential diagnosis.
18. When is an examination in the sleep laboratory necessary and what happens there?
Important symptoms of disturbed sleep are sleepiness during the day, pronounced concentration disorders, morning headaches, heavy snoring and sweating, and irregular breathing during sleep. Diagnosis and treatment regimen are made by experienced physicians who have the possibility of interdisciplinary cooperation with psychiatrists, neurologists, lung specialists, ear, nose and throat specialists and psychologists. The examination in a sleep laboratory serves to measure physiological functions during sleep. This diagnostic procedure usually requires two nights in the sleep laboratory, during which all sleep parameters are carefully monitored and recorded. This registration is safe and painless and is performed in a quiet room with the help of trained personnel. For this purpose, sensors are placed on the head, on the sides of the eyes and on the extremities. In addition, the respiratory movements of the chest and abdomen are recorded, as well as the oxygen content of the blood, cardiac activity and other physiological values that are of interest in establishing the diagnosis. Video recording is also often performed to record particular nocturnal behaviors, such as sleepwalking. See sleep laboratory. After the recordings in the sleep laboratory, the data material must be evaluated in relation to the various sleep phases and pathological factors. This work requires a large investment of time. The overall picture from the results of the sleep derivation (technical term: polysomnography), the medical history, the physical examination findings and other laboratory data enables the physician trained in sleep medicine to make a diagnosis and recommend treatment.