With sleep-supporting day-activities, fixed sleeping times and positive thoughts you can find the way to a relaxing sleep easily and fast again.
Many sleeping problems depends on the everyday life, which isn’t consistent with the “inner clock” - especially shift workers or after a long flight over various time zones have problems with it. They are quite awake even if it’s very late at night. This is a disorder of your private wake-sleep cycle.
But there are also people, whose rhythm isn’t synchronous with the environment. Many people suffer from sleeping problems, but they and their therapists don’t know the reason(s) for it.
People are different and so everyone has an own wake-sleep-rhythm. Sleep researchers discriminate two types of problem: the “larks” and the “owls”. These ones’ biorhythm is badly shifted in comparison with the average population.
Another problem area are elderly. The natural wake-sleep cycle is weakening with increasing age. There isn’t a clear boundary between the sleeping and woken phases like they appear on young people.