For example, growth hormone – somatotropin – is released mostly during deep sleep. And if the child does not have enough deep sleep for a long time, then there is a delay in weight gain and growth retardation. Children with sleep disorders in infancy after 3 years of age have more behavioral problems, and their sleep disorders often persist into the future.
The sleep of a child in the first years of life is significantly different from the sleep of an adult. In particular, this applies to its duration. A newborn sleeps a lot – 18 hours a day, an infant at the age of six months – 14,5 hours, a one-year-old baby – 14 hours, and a child at the age of 6 years – 11 hours. Only by the age of 16 does the child begin to sleep “like an adult” – about 8 hours.
Another feature is polyphasic – the onset of sleep several times during the day. A long nighttime sleep period appears in children after 2 months of age, after six months the child sleeps 2-3 times during the day, at the age of 1 to 2 years there is a transition to a one-time daytime sleep. No naps start at age 3, although doctors recommend keeping naps for as long as possible (before school).
The third distinguishing feature of childhood sleep is a large amount of in the dream sleep. Newborns spend half of their sleep time in so-called REM sleep. It is believed that it is during this phase of sleep that a person most often sees dreams. At six months, REM sleep already occupies only 30% of the time of all sleep, and “like in adults” – 25% it becomes by the age of 15. Such an excessive amount of REM sleep in the first years of life is associated with its role in the organization of mental activity – after all, at this time the child receives a huge amount of new information that needs to be evaluated, remembered, and associated with previous experience.
A sleep cycle lasts approximately 90-100 minutes.
- In one night there are from 4 to 6 cycles, depending on the duration of sleep. The first half of sleep is characterized by mostly deep sleep, and in the second half, light and paradoxical sleep mostly alternate.
- A good night’s sleep is when the child goes to bed without problems, sleeps through the night without waking up, and wakes up in the morning on his own. During the day, the child eats well, remains calm. If the child is restless and irritable, he may not be sleeping well.
- There are phases when the child wakes up, and this is normal; but as soon as parents are involved in this process, and cases of lack of sleep are repeated, this can mean sleep disturbance.
- Each person has their own needs for the amount of sleep. The way a person sleeps, the total amount of time needed for sleep, the duration of each cycle – all these parameters are purely individual, programmed by the brain and probably genetically organized. They are produced throughout life, from the prenatal period to old age.