How Children Sleep
In my article series Sleep Coaching (®Klösch & Holzinger) Outlined published here on Medium, I have presented in a nutshell our methodology to preserve healthy sleep and to find back to it. In the five parts of this article series, we saw the effect of sleep, how sleep deprivation affects our health and through which measures we can find back to our innate ability to sleep well. In this present article I would like to emphasize the differences between the adult sleep and the sleep of our children. Further, I will go into the details of how unhealthy sleep can affect a child, which consequences sleep deprivation can have on children’s physical and mental health and which measures can help to prevent children to experience unhealthy sleep. I highly recommend to read through the five chapters of the main article Sleep Coaching if you want to go deeper into the science of sleep and the method of sleep coaching. Part one is freely available and shows which inner attitude stands behind our sleep coaching (®Klösch & Holzinger) method and how this attitude already promotes healthy sleep. As for this article, it is a summary of a book that I am currently preparing. If you want to find out more about children’s sleep, please follow the channel of my Institute on Facebook, I will keep you informed there about all new publications. As an alternative, you also will get updates directly on our website: www.traum.ac.at. Now, let me go into the topic of how children sleep.
In the mother’s womb
Sleep has only two stages in newborns, but is has been observed that even unborn babies already show Rapid Eye Movements in their mother’s wombs. We therefore can assume that even in the unborn we find the 2 sleep stages as for newborns: deep sleep (also called quiet sleep, which will later split into different sleep stages within older children) and active sleep (comparable to REM-Sleep for adults). Which kind of dreams they do experience will most probably always remain a mystery!
For the mothers, it is very important to keep their sleep healthy during pregnancy, which is not always an easy task. Especially in the last months of pregnancy, many experience difficulties in finding the right sleeping position, especially the mothers who previously used to sleep on the stomach. Further, if the life situation of the mother is a difficult one, she might experience a lot of stress, which can lead to insomnias and anxieties: this actually can affect their unborn child.
Children spend much more time sleeping than adults and we also observe much longer REM-sleep phases than for adults: for newborn babies, REM-sleep makes up about 50% of sleep. Typically, their sleep begins with REM sleep before non-REM sleep (which is the other way round for adults). Over the first 2 years, the REM sleep percentage drops to around 20–25%. Under normal circumstances, this proportion remains constant into old age. REM-Sleep is the famous rapid eye movement sleep during which the more vivid dreams occur. Dreams can be considered to be created by our unconscious out of day residues, but to be more precise, I need to explain how our memory works.
During the day, we store all the information in our short-term memory. If we are confronted to a lot of information throughout the day, we start to encounter some difficulties focusing which leads to feeling tired. While sleeping, in the REM-sleep phase all the information we have accumulated while awake is transferred from our short- to our long-term memory. While this process happens, information and experience deemed unimportant or elements which we already know are being entirely deleted. This explains really well why toddlers need to dream more often and for a way longer period: For them, everything they experience is new, so everything needs to be transferred to long term memory. This is a lot of “data” transfer!
While this process of memory consolidation takes place, feelings and abstract thoughts are believed to being “translated” into images and stored as such, as that way, memory can be accessed faster (as fast as it takes to look at an image) and needs less storage space in our brain (less synaptic connection). Those abstract images are probably mostly what we see when we dream: this is the best theory about dream imagery we have until now, but of course, it is very difficult to prove it which is why not all scientists endorse this theory yet. I believe it really makes sense and it would explain well why dreams often involve such cryptic imagery.
Now, what happens to a toddler who does not sleep enough and thus, does not get enough REM-sleep? Unfortunately, its memory will not be consolidated properly, meaning: it does not learn as much and as fast as it could and while awake, it will have a harder time focusing on new experiences, because it is tired and there is not enough space left in its short-term memory to take in much more information. This tiredness will make it cranky and it might cry more out of frustration.
And what about the deep sleep phase? As stated above, newborn experience only two sleep phases: one REM-phase (also called active phase) and one deep sleep phase (also called quiet sleep or inactive phase). The deep sleep phase is when regenerating happens and the immune system gets strengthened. Most important is: that is when toddlers and actually all children grow.
So how much sleep is enough sleep for toddlers?
In the first 4 weeks, a newborn will need about 15 to 18 hours of sleep per 24 hours. At this age, they still have a polyphasic sleep, which means that they do not get their whole amount of sleep all at one time unlike adults who commonly sleep straight through the night (monophasic sleep). In general, toddlers sleep about 2 hours, they then wake up to eat and to make new experiences before they sleep again to process all the new experience and the energy intake (milk).
It is important to already get them used to daytime = light and nighttime = dark. This will set their internal clock (circadian rhythm) and in the future, their body will naturally adapt to sleep when it is dark. Some studies also prove that a balanced circadian rhythm prevents depressions, which is why setting the circadian rhythm as soon as possible might prevent depressions in older children or even in adults.
A 1 to 4 months old toddler will sleep for about 14 to 15 hours per 24 hours. Its sleep is still polyphasic, but in the night, it might already sleep straight for about 6 hours.
From 4 months to 12 months, toddlers will progressively start to sleep a little less, keeping them sleeping for about 14 hours as long as possible is good, but all is fine as long they get more than 12 hours of sleep. From the age of 4 months a baby will start to produce the sleep hormone melatonin, so now it is even more important to keep the room dark at night, as light prevents the release of melatonin, thus, at night, it disrupts the circadian rhythm (which regulates the 24 hours day cycle).
Many toddlers have difficulty sleeping due to physical problems: colics for example are very common. It is very important to consult a physiologist if the symptoms persist, as for the toddlers colics are not only painful but also sleep depriving.
To promote sleep, the right temperature in the bedroom is also very important. Even toddlers in the first 6 months do not need much higher temperatures than adults in the bedroom: from 18 to 21 degrees Celsius (65 to 72 degrees Fahrenheit) is way enough (later and for adults I would highly recommend to keep the room temperature at about 18 degrees Celsius (65 degrees Fahrenheit). As for the blankets, make them not too heavy so the baby can move freely, also do not pile up blankets and stuffed animals in their crib. Avoiding overheating is very important so watch out: if the baby sweats too much, take a thinner blanket or if it’s summertime, use a fan or air condition in the room (do not direct the air stream directly towards the toddler, your goal is to reduce the room temperature altogether). Room temperature as much as sleeping position is also helping to reduce the risk to the Sudden infant death syndrome (SIDS). Avoid them sleeping on a couch or in your arms as much as possible: their beds are perfectly fit to their needs!
Toddlers are not as sensitive to noise as you might think: basic noises like soft music or you making the dishes and talking with the rest of the family does not disrupt a toddler’s sleep. Avoid sudden noises though, those might wake it up. If you expose a toddler to a normal level of background noises you can avoid it to become oversensitive to noises later on, which might become important for the whole family to have a normal lifestyle (with all the noise it implies) even in the presence of a small child at home.
Now is also the time to get toddlers to being used to fall asleep by themselves. They might start nodding in your arms, but then, it is time for them to be put in their crib to fall asleep. This helps them to get used to connect the idea of sleep with the bed as soon as possible.
As progressively at the age of 1 year, toddlers start sleeping more at night and less often during the day, they will carry on needing an afternoon nap, but will skip morning and evening naps, going for now into bi-phasic sleep, i.e. two sleeping periods: one in the night and one in the afternoon. Until the age of three the sleeping hours needed will progressively be reduced to about 11 to 13 hours and they will also move away from the parent’s bedroom to their own.
By observing their child, parents will quickly find out how much sleep it actually needs. In the course of the pre-school and primary school years, the need for sleep decreases. With some children it is necessary to keep the afternoon nap until the 5th year, with others it can be stopped much earlier. Keeping a sleep diary can be helpful to better observe the child’s sleep pattern. With this tool in hands, the time to go to bed can easily be calculated: time to get up minus the hours of sleep required equals bedtime.
On the average, pre-school children need about 10 to 11 hours of sleep, but as stated above, this strongly varies individually (also the average of 7 for adults is only an average and might not correspond to every adult’s needs).
Pre-school children still experience a lot of new things and learn every day, which is increasing their need for REM-sleep. Meeting other children their age is also very helpful to strengthen their social skills and to learn interaction not only with their adult parents but with equals. Reading the faces of other children, understanding which action leads to which reaction is a very important part of what they are learning at this age i.e., they learn the non-verbal communication as much as the language. What can lead to problems especially for children living in apartments and having no gardens, is that deep sleep is promoted by physical tiredness. Being outdoors and playing helps them to develop motoric skills while at the same time, they get physically tired, which in the evening, increases the need to sleep (sleep pressure): they fall asleep faster. Also, outdoor activities makes them get enough sunlight during the day, which helps them to produce vitamin D which in return is needed to produce serotonin (a “happy Hormone”) which in return is needed to produce melatonin (sleep hormone).
Another method to promote sleep is a bedtime routine, we call it a bedtime ritual. It can start with washing or bathing, then brushing teeth, getting the pyjama on and then one of the parents reading a bedtime story. This routine, which ever it is, should be the same every day. This will already make the body automatically go into sleep mode in the very moment the bedtime ritual starts. BTW: Playing in the bed should be avoided, as the bed should be associated with sleep only.
Having made enough news experiences and being physically tired adds to the effectiveness of bedtime rituals. Further, keep the lights dimmed: as stated above, the sleep hormone melatonin can be released only when it is dark.
Many children wake up at night, there can be many reasons to it, so it is impossible to address all of them in this short article. I would like to address the nightmare topic, as this is quite common and though in most cases, occasional nightmares are a harmless event, if experienced more often, they disrupt a child’s sleep pattern really badly. As adults, we are used to the world we live in which is why we sometimes can only hardly fathom how scary some things might appear to small kids. When they dream at night, some things they saw or experienced during the day might lead to nightmares, which wake them up with a deep feeling of fear. Very often pre-school children have still difficulties to express their dreams even if they remember them. Just let them talk about the nightmare and reassure them. Many of the imageries and dream plots in children’s nightmares are simple but they involve a lot of complex feelings and thoughts. Interestingly, when an adult scared a child, this scary figure often is translated by the child’s dream imagery into an animal: as an example, a dreamt threatening bear can represent the tall and strong neighbor.
Further, children under the age of 4 have a hard time making the difference between a dream and reality. This is how telling to children at this age that “it was just a dream” is not reassuring at all to them. If they dreamt of a nasty fox, just show them images of cute and kind foxes, making the threat appear harmless. Also making sure that the parents can protect them and are always there when needed is very helpful. A child has the inherent knowledge that it needs protection, thus, making a child feel safe means showing presence and strength when needed. A morning routine at breakfast including talking about the dreams that the children remember can also be very helpful in discovering what is happening in the unconscious of a child, and maybe even help to uncover possible issues. Further, talking about dreams and nightmares on a daily basis can boost a child’s creativity.
The urge to go to the toilet also is a reason for waking up at night. This can sometimes be prevented if the child drinks enough during daytime and not anymore at least two hours before bedtime. Nocturnal enuresis (bed wetting) can often be avoided through this. Of course, for pre-school kids it is a learning process to be able to wake up when feeling a pressure in their bladder and also the bladder needs to be trained in order to hold back better (also a daytime learning process). Many children also dream of going to the toilet and wake up when they realize that in reality, they still were in bed. This issue usually gets solved quickly, but not blame the children, as this might worsen the situation. If this problem persists and happens on a regular base, you might want to check with your pediatrician to find out if there is a physical condition to it. There also might be a psychological reason for it, in this case, a therapist might be able to help. Often it is the fear that it could happen that actually makes it happen.
There is currently a lot of debate around the topic “sugar” and as I am not a nutritionist, I will not go into detail if sugar should be avoided altogether, but in the evening, eating sweets for sure disrupts sleep because it provides a boost of energy preventing a child (and also an adult!) to come to rest. The same goes for chocolate in the evening, not only does it contain sugar it also contains caffeine and keeps children awake and active. If some evening snack is needed, nuts are a good, healthy alternative which also promotes sleep.
Primary school age
Here start the real problems with sleep: children do not want to go to bed early enough for getting up in time for school in the morning. At this age, they still need at least 9–10 hours of sleep.
The issue at hand is a systemic one: school and most jobs are based on the circadian rhythm of morning people. Each individual is different though, which means that some of us are early birds, while others are late night owls. Of course, whatever natural circadian rhythm you child has, if you got it used at pre-school age to get up early, it might help a lot now, even if your child’s nature is that of an owl. It still will have a harder time to get sleepy early enough in the evening than children who are early birds naturally. Chronobiologists suggest it would be way better for children if they could choose at which time they want to go to school, for many it would be better to not start before 10 AM. As it is not in our hands to influence when schools actually start their classes, we have to deal with the early hours. For parents which have a job that starts early too, there is not much of a choice in anyway: children need to get up early in order to go to school.
How is it possible to easily cope with it, if your child happens to be an owl type of person? First, do not blame your child for it, it is its very nature. The circadian rhythm can be trained to adapt to an early morning lifestyle. For training the circadian rhythm it is important to start as early as possible, already at pre-school age. The circadian rhythm also is determining when a person gets hungry, keep very regular times for breakfast, lunch and dinner. Dinner should be eaten as early as possible, in order to have at least 4 hours between dinner and bedtime.
There is another cycle going parallel through the day with us: the BRAC (basic rest activity cycle). This last for about 90 minutes as an average. At night, the BRAC determines our sleep pattern. One sleep cycle is one BRAC long, which means that at the end of each BRAC we experience REM sleep, after which we have a micro-awakening (most do not realize it) and we dive back into deeper sleep stages, until the next REM sleep cycle. It is way easier to wake up after a REM sleep phase than in the middle of a deep sleep phase. Therefore, if a child (or also an adult), has a very hard time to wake up at a certain time (let us say at 7 AM as an example), then it might help to set the alarm a little earlier. Try with tranches of 10 minutes to find out the exact time when your child has a REM sleep phase ending: it might lead to the child needing to wake up at 6 AM instead of 7 AM in order to wake up more alert and happier, i.e., in the right moment of the BRAC.
While adults usually are more apathic when overtired, a child deprived of sleep may show many different symptoms: sleep deprived children can show ADHD-like symptoms, an increased aggressivity and learning difficulties. As a more physical symptom, sleep deprived children also have a higher prevalence for obesity (linked to it is diabetes type 2). Body and mind simply go off balance.
Keeping children into a proper, regular rhythm preserves healthy sleep and health altogether. If on school free days children are allowed to stay up much longer and to get up much later, they will encounter even more difficulties to face the early getting up on school days. The same goes for breakfast, lunch and dinner time: the circadian rhythm should be kept the same on a day off in order to not disrupt it.
After school it is time to grant children time to play, if possible, outdoors and with friends their age. I will get deeper into this topic below, when addressing the important topic of stress.
The bedtime rituals might change a bit and adapted to the needs of their age (they can read their books themselves now!) but a bedtime ritual is as useful as it was before and even still can be for adults. One new topic has to be addressed: the usage of social media and computer games. The blue light on screens is disrupting sleep, therefore it is good to shut down all screens about an hour before bedtime. Additionally, games can be very stimulating, fighting games even can activate the fight or flight reaction of the body, which puts the body in a very active mode preventing sleep pressure to occur.
Ideally, teenagers need about 8 hours of sleep, but most of them get way less than that and suffer from what can be considered a constant social jet lag. They have a lot to work for school and at the same time, they need to interact a lot with their friends to be sure to find acceptance. Their time management becomes very difficult due to those two factors, while at the same time, their bodies go through a massive hormonal transition that makes sleep even more important. The issue is that the hormonal transition also has an effect on their circadian rhythm: they get tired later, while they still need to get up early for school. Some teenagers have phases in which they need nearly 14 hours of sleep to cope with that transition, while actually often getting no more than 6 hours of sleep. That leads to them occasionally sleeping a lot on weekends, which has nothing to do with laziness: it is needed for their bodies to readjust to the change in their hormonal balance. Of course, this should happen only occasionally, if the need for an increased amount of sleeping hours persists, then there might be an issue at hand that needs to be addressed: some physical issues can lead to this, but also a depression or a burn out could be the cause.
Controlling their use of social media helps a little, so they do not chat until late with their friends and sleep even less. Outdoor physical activities like sports also help them to increase sleep pressure and become tired a bit earlier in the evening.
Stress, a sleep thief for all ages
Many parents look back at their own childhood from a romanticized viewpoint and tend to deny how stressful childhood can be. Actually, many sleep issues during childhood and adolescence are stress related. From toddlers to teenagers: a stressful environment is stressful for children too. As an example: poverty can mean a high level of stress also for children. Even the very young ones feel how their parents struggle, they feel helpless, sometimes guilty, and in severe cases also threatened by it. Starvation might be a threat barely known in our countries, but malnutrition and social marginalization unfortunately is quite widespread and much underestimated. In Germany, which is considered one of the richest countries in the world, about 20% of kids live in poverty. At a young age, they feel the stress and the struggle of the parents, which already can prevent healthy sleep. The food is not of high quality, so they often lack vitamins and minerals needed for proper growth, and later on, they cannot make as many experiences (connection of neurons, development of skills) as other kids, as most activities (museum, sports and so on) cost money. The frustration and stress of poverty grows as the children get older, as they then understand the threatening position in which they are. Of course, poverty is not the only stressor a child can encounter. (I will not go into the topics of war, neglect and domestic abuse, as this is evidently a traumatizing event beyond anything that could be explained in a few lines.) Even for the 80% of children not facing the stressor poverty, there are many elements of life that can affect their stress level. It can be an argument with friends, a disease affecting a family member, accidents, death within friends or families (even the death of a pet can be traumatizing), natural disasters, mobbing, bullying, pressure to perform at school, parents arguing or struggling at work and so on. In many cases, it can help the child to better cope with difficult situations when the parents don’t hide their own stress and talk about negative events that happened. Of course, how and what is possible to say depends on how old the child is, but it often is more harmful to hide bad things from a child and making it wonder why everybody is so stressed, than to actually tell to it a version of the truth that the child is old enough to understand (actually, children understand way more than adults believe, they “have a feel” for a situation going sideways).
Now let’s us go into more details about how stress affects the health and the sleep of children.
Stress response is meant to last for a short period of time, it is a function of our body that allows us to survive a threatening situation: for example, the need to fight or to flee from a danger, like the attack of a wild animal. We need to become more alert, faster and for reaching the level needed, we need to mobilize as much energy as possible. In order for doing that, our body and that of our children release the stress hormone cortisol and it leads to the following:
· Mobilization of energy
· Increased cardio vascular tone
· Suppression of digestion
· Suppression of growth
· Suppression of reproduction
· Enhancements of immune system
· Sharpening of cognition (high alertness)
All this is good for us if we actually act on it, use up all the stress hormones and go back to normal after a short time, but chronic stress leads to higher cortisol levels on a long term, which has a totally different effect:
· Suppression of digestion (leads to ulcers, fat deposition, the repair system is down, so the bacteria h-pilori can do its harm)
· Insulin resistant diabetes
· Suppression of growth (only rarely and in extreme cases)
· Delaying of puberty
· Weakening of the immune system (opposed to what happens with short term stress response)
· Chronical stress affects the hippocampus, thus it prevents memory consolidation during REM sleep
· Sleep deprivation, anxieties and depression
How can children relax and get over stressful situations?
Children relax by playing and interacting with other children. It happens often nowadays that children have so many free time activities booked, that there is no time left for them to just meet friends and naturally, playfully take it from there and relax in the process. They also need to share their problems and be taken seriously by family members. Social support by good friends helps a lot to overcome stress, but beware of bad friends, as disappointment by friends is even more harmful than having no friends at all. This is valid for small children, who need to trust, as much as for teenagers, who need a group to feel acceptance. Social media acquaintances do not have the same effect, real contacts are needed for experiencing the soothing feeling of safety.
Pandemic related stress
As you probably already found out by reading the previous paragraph on stress, the pandemic and the measures implemented to fight the virus have a massive impact on children’s (and adults’) stress levels. Some studies are currently being made by psychologists to assess the effects and we already know that many suffer from depressions (close to 50%), anxieties and sleep deprivation. I myself participate in such an international study and we will soon be publishing our results. To us, the mental health issues we are currently facing might be an issue our children and young adults will be facing for many years to come. We have noticed that the symptoms shown are the ones we usually see in patients suffering from Post-Traumatic Stress Disorders (PTSD). As the measures in place differ in every country or even region, I will set here some recommendations about how to counter some of the effects, but please make sure that the measures I recommend are allowed in the place you live before implementing them. I am not calling up on you to break some rules, so please only follow my advice if it is possible to do so where you live.
· Make sure your children keep contact to their friends, if possible physical contact, not only virtual one.
· Let them play outdoors whenever possible without masks, so their get as much sunlight as possible brains get enough oxygen.
· Avoid wearing masks in their presence (connecting to people involves reading facial expressions and childhood is the time we learn this important skill).
· Play with them as much as possible, if their friends are not allowed to do so.
· Do not make them see too many news inducing fears of viruses. Explain to them how children are nearly not affected by this disease to avoid them fearing it.
· If you as parents also experience depression or anxieties due to the situation, try to get some help as children feel very well what their parents go through and often suffer from it more than they show.
· Do not blame your children if someone in the family gets the virus: guilt can grow to a major psychological problem and lead to chronic stress.
As for many other stressors, the main, most important measure is to give to children the feeling of safety and the comfort of a loving family.
Basic helping tools in short
1) For babies: avoid lying them on their stomach, do not let them fall asleep in your arms (thus promoting independence when falling asleep); Do not heat the children’s room to over 18 degrees Celsius (65 Fahrenheit) -avoid overheating the baby.
2) Clarification of colic and any pain in preverbal infants and young children.
3) Attempt to eliminate the basic physical problem for sleep disorders, possibly also through surgical interventions, if necessary — for example: sleep apnea: In a study, sleep and breathing patterns returned to normal after a tonsillectomy (removal of tonsils).
4) If there is a comorbidity (e.g. sleep disorders and depression), treatment of the underlying disorder or both disorders.
5) TV / Media Consumption: Recommendations from the American Academy of Pediatrics suggest that children should watch television no more than 2 hours per day to avoid sleep disorders (accumulative media effects must be taken into account).
6) No more direct screen light at least one hour before bedtime. Before sleeping it is helpful to read (no school book, just relaxing literature)
7) Let TV, computer, laptop, tablet and cell phone enter the room as late as possible, as once those are there, kids don’t want to appear “uncool” and therefore don’t want to be the first to break up chats with their friends.
8) Avoid other factors that interfere with healthy sleep (coffee, cola, energy drinks, etc.)
9) A good way to find out what is taking sleep away from our children is to talk to them at the breakfast table as well. Dreams and nightmares should be told and briefly discussed, the contents of which are often revealing when it comes to the psyche of children. In the dream worlds, fears, bullying experiences etc. are often dealt with, which might otherwise not openly be addressed by the child.
10) Provide a general atmosphere for discussion and trust in which the child has the feeling that it can confide. In addition, potentially traumatic experiences should be discussed quickly.
11) Establish healthy sleep practices (such as establishing a consistent sleep-wake rhythm with the same or little different sleeping and waking times between weekdays and on weekends, determining the child’s need for sleep and allowing the child to get enough, but not excessive, sleep, introduce soothing bedtime rituals etc.)
12) During sleepwalking (a parasomnia), care must be taken in any case to avoid the risk of injury. A wet rag near the bed can sometimes help to wake the child up when it walks barefoot on it. As in most cases of insomnia in children, a safe, stress-free environment has a positive effect on reducing parasomnias.
Children have the innate ability to sleep well, but many elements in life can disrupt their healthy sleep and affect also their future adult life. Taking care of a child’s sleep is taking care of its future and it will positively affect all of its life. Children and teenagers are more resilient if they slept enough, so when they sleep more than adults, it is normal and they should not be labelled lazy for doing so. Provided with a safe environment and good friends to play with (possibly outdoors), nothing should stand in their way to experience a happy life full of energy.
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