Sleep myths
(see: Good sleep for good learning for a more comprehensive list)
(Fonte)
  1. Myth: Since we feel rested after sleep, sleep must be for resting. Ask anyone, even a student of medicine: What is the role of sleep? Nearly everyone will tell you: Sleep is for rest. Fact: Sleep is for optimizing the structure of memories. If it was for rest or energy saving, we would cover the saving by consuming just one apple per night. To effectively encode memories, mammals, birds and even reptiles need to turn off the thinking and do some housekeeping in their brains. This is vital for survival. This is why the evolution produced a defense mechanism against skipping sleep. If we do not get sleep, we feel miserable. We are not actually as wasted as we feel, the damage can be quickly repaired by getting a good night sleep. Our health may not suffer as much as our learning and intelligence. Feeling wasted in sleep deprivation is the result of our brain dishing punishment for not sticking to the rules of an intelligent form of life. Let the memory do restructuring in its programmed time
  2. Myth: Sleeping pills will help you sleep better. Fact: Benzodiazepines can help you sleep, but this sleep is of far less quality than naturally induced sleep (the term "sleeping pill" here does not apply to sleep-inducing supplements such as melatonin, minerals, or herbal preparations). Not only are benzodiazepines disruptive to the natural sleep stage sequence. They are also addictive and subject to tachyphylaxis (the more you take the more you need to take). Sleeping pills can be useful in circumstances where sleep is medically vital, and cannot be achieved by other means. Otherwise, avoid sleeping pills whenever possible
  3. Myth: Silence and darkness are vital for sleep. This may be the number one advice for insomniacs: use your sleeping room for sleep only, keep it dark and quiet. Fact: Silence and darkness indeed make it easier to fall asleep. They may also help maintain sleep when it is superficial. However, they are not vital. Moreover, for millions of insomniacs, focusing on peaceful sleeping place obscures the big picture: the most important factor that makes us sleep well, assuming good health, is the adherence to one's natural circadian rhythm! People who go to sleep along their natural rhythm can often sleep well in bright sunshine. They can also show remarkable tolerance to a variety of noises (e.g. loud TV, family chatter, the outside window noise, etc.). This is all possible thanks to the sensory gating that occurs during sleep executed "in phase". Absence of sensory gating in "wrong phase" sleep can easily be demonstrated by lesser changes to AEPs (auditory evoked potentials) registered at various parts of the auditory pathway in the brain. Noises will wake you up if you fail to enter deeper stages of sleep, and this failure nearly always comes from sleeping at the wrong circadian phase (e.g. going to sleep too early). If you suffer from insomnia, focus on understanding your natural sleep rhythm. Peaceful sleeping place is secondary (except in cases of impaired sensory gating as in some elderly). Insomniacs running their daily ritual of perfect darkness, quiet,  stresslessness and sheep-counting are like a stranded driver hoping for fair winds instead of looking for the nearest gas station. Even worse, if you keep your place peaceful, you run the risk of falling asleep early enough to be reawakened by the quick elimination of the homeostatic component of sleep. Learn the principles of healthy sleep that will make you sleep in all conditions. Only then focus on making your sleeping place as peaceful as possible. For more see: Good sleep, good learning
  4. Myth: People are of morning or evening type. Fact: This is more of a misnomer than a myth. Evening type people, with chronotherapy, can easily be made to wake up with the sun. What people really differ in is the period of their body clock, as well as the sensitivity to and availability of stimuli that reset that rhythm (e.g. light, activity, stress, etc.). People with an unusually long natural day and low sensitivity to resetting stimuli will tend to work late and wake up late. Hence the tendency to call them "evening type". Those people do not actually prefer evenings, they simply prefer longer working days. The lifestyle affects the body clock as well. A transition from a farmer's lifestyle to a student's lifestyle will result in a slight change to the sleeping rhythm. This is why so many students feel as if they were of the evening type
  5. Myth: Avoid naps. Fact: Naps may indeed worsen insomnia in people suffering from DSPS, esp. if taken too late in the day. Otherwise, naps are highly beneficial to intellectual performance. It is possible to take naps early in the day without affecting one's sleeping rhythm. Those naps must fall before or inside the so-called dead zone where a nap does not produce a phase response (i.e. shift in the circadian rhythm) 
  6. Myth: Night shifts are unhealthy. Fact: People working in night shifts are often forced out of work by various ailments such as a heart condition. However, it is not night shifts that are harmful. It is the constant switching of the sleep rhythm from day to night and vice versa. It would be far healthier to let night shift people develop their own regular rhythm in which they would stay awake throughout the night. It is not night wakefulness that is harmful. It is the way we force our body do things it does not want to do
  7. Myth: Going to bed at the same time is good for you. Fact: Many sleep experts recommend going to sleep at the same time every day. Regular rhythm is indeed a form of chronotherapy recommended in many circadian rhythm problems. However, people with severe DSPS may simply find it impossible to go to sleep at the same time everyday. Such forced attempts will only result in a self-feeding cycle of stress and insomnia. In such cases, the struggle with one's own rhythm is simply unhealthy. Unfortunately, people suffering from DSPS are often forced into a "natural" rhythm by their professional and family obligations
  8. Myth: People who sleep less live longer. In 2002, Dr Kripke compared the length of sleep with longevity (1982 data from a cancer risk survey). He figured out that those who sleep 6-7 hours live longer than those who sleep 8 hours and more. No wonder that a message started spreading that those who sleep less live longer. Fact: The best longevity prognosis is ensured by sleeping in compliance with one's natural body rhythm. Those who stick to their own good rhythm often sleep less because their sleep is better structured (and thus more refreshing). "Naturally sleeping" people live longer. Those who sleep against their body call, often need to clock more hours and still do not feel refreshed. Moreover, disease is often correlated with increased demand for sleep. Infectious diseases are renowned for a dramatic change in sleep patterns. When in coma, you are not likely to be adding years to your life. Correlation is not causation
  9. Myth: A nap is a sign of weakness. Fact: A nap is not a sign of weakness, ill-health, laziness or lack of vigor. It is a philogenetic remnant of a biphasic sleeping rhythm. Not all people experience a significant mid-day slump in mental performance. It may be well masked by activity, stress, contact with people, sport, etc. However, if you experience a slump around the 5th to 8th hour of your day, taking a nap can dramatically boost your performance in the second half of the day
  10. Myth: Alarm clock can help you regulate the sleep rhythm. Fact: An alarm clock can help you push your sleep rhythm into the desired framework, but it will rarely help you accomplish a healthy sleep rhythm. The only tried-and-true way to accomplish a healthy sleep and a healthy sleep rhythm is to go to sleep only when you are truly sleepy, and to wake up naturally without external intervention
  11. Myth: Being late for school is bad. Fact: Kids who persistently cannot wake up for school should be left alone. Their fresh mind and health are far more important. 60% of kids under 18 complain of daytime tiredness and 15% fall asleep at school (US, 1998). Parents who regularly punish their kids for being late for school should immediately consult a sleep expert as well as seek help in attenuating the psychological effects of the trauma resulting from the never ending cycle of stress, sleepiness and punishment
  12. Myth: Being late for school is a sign of laziness. Fact: If a young person suffers from DSPS, it may have perpetual problems with getting up for school in time. Those kids are often actually brighter than average and are by no means lazy. However, their optimum circadian time for intellectual work comes after the school or even late into the evening. At school they are drowsy and slow and simply waste their time. If chronotherapy does not help, parents should consider later school hours or even home-schooling
  13. Myth: We can sleep 3 hours per day. Many people enviously read about Tesla's or Edison's sleeping habits and hope they could train themselves to sleep only 3 hours per day having far more time for other activities. Fact: This might work if you plan to party all the time. And if your health is not a consideration. And if your intellectual capacity is not at stake. You can sleep 3 hours and survive. However, if your aspirations go beyond that, you should rather sleep exactly as much as your body wants. That is an intelligent man's optimum. With your improved health and intellectual performance, your lifetime gains will be immense
  14. Myth: We can adapt to polyphasic sleep. Looking at the life of sailors, many people believe they can adopt polyphasic sleep and save many hours per day. In polyphasic sleep, you take only 4-5 short naps during the day totaling less than 4 hours. There are many "systems" differing in the arrangement of naps. There are also many young people ready to suffer the pains to see it work. Although a vast majority will drop out, a small circle of the most stubborn ones will survive a few months and will perpetuate the myth with a detriment to public health. Fact: We are basically biphasic and all attempts to change the inbuilt rhythm will result in loss of health, time, and mental capacity. A simple rule is: when sleepy, go to sleep; while asleep, continue uninterrupted
  15. Myth: Sleep before midnight is more valuable. Fact: Sleep is most valuable if it comes at the time planned by your own body clock mechanism. If you are not sleepy before midnight, forcing yourself can actually ruin your night if you wake up early
  16. Myth: The body will always crave excess sleep as it craves excess food. Some people draw a parallel between our tendency to overeat with sleep. They believe that if we let the body dictate the amount of sleep, it will always ask for more than needed. As a result, they prefer to cut sleep short with an alarm clock to "optimize" the amount of sleep they get. Fact: Unlike storage of fat, there seems to be little evolutionary benefit to extra sleep. Probably, our typical 6-8 hour sleep is just enough to do all "neural housekeeping". People with sleep deficit may indeed tend to sleep obscenely long. However, once they catch up and get into the rhythm, the length of their sleep is actually likely to decrease
  17. Myth: Magnesium, folates, and other supplements can help you sleep better. Fact: Nutrients needed for good health are also good for sleep. However, supplementation is not likely to play a significant role in resolving your sleep problems. Vitamins may help if you are in deficit, but a vast majority of sleep disorders in society come from the lack of respect or understanding of the circadian rhythm. Only wisely administered melatonin is known to have a beneficial effect on the advancement of sleep phase. If you are having problems with sleep, read Good sleep for good life. As for supplements, stick to a standard healthy diet. That should suffice
  18. Myth: It is best to wake up with the sun. Fact: You should wake up at the time when your body decides it got enough of sleep. If this happens to be midday, a curtain over the window will prevent you from being woken up by the sun. At the same time sun may help you reset your body clock and help you wake up earlier. People who wake up naturally with the sun are indeed among the healthiest creatures on the planet. However, if you do not wake up naturally before 4 am, trying to do so with the help of an alarm clock will only add misery to your life
  19. Myth: You cannot change the inherent period length of your body clock. Fact: With various chronotherapeutic tricks it is possible to change the period of the clock slightly. It can be reset or advanced harmlessly by means of melatonin, bright light, exercise, meal timing, etc. It can also be reset in a less healthy way: with an alarm clock. However, significant lifestyle changes may be needed to resolve severe cases of DSPS or ASPS. The therapy may be stressful, and the slightest deviation from the therapeutic regimen may result in the relapse to an undesirable rhythm. Those who employ free-running sleep may take the easiest way out of the period length problem: stick to the period that is the natural outcome of your current lifestyle 

 

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