Sleep in humans, as in any animal, is usually caused by fatigue and overwork. This causes the need for peace and relaxation. In a state of sleep, the body is weakened after hours of active activity and the necessary energy and strength gradually returns to start again the actions that make up life. But why do people dream? When the nervous system is exhausted, this leads to slowed blood circulation, which, in turn, slows down the activity of all vital functions. As a result, attention and will are lost; they are replaced by oblivion or sleep. A person falling asleep temporarily ceases to have a connection with the outside world, in part, he seems to lose his awareness of his being, any external phenomena and objects no longer affect him. And only the brain actively continues its mental activity, thanks to which dreams and dreams come.
During sleep, nerves no longer transmit sensations to the brain. Of all the organs present, vision is primarily tired; it is the eyes that require rest, rest and sleep in the first place. But at the same time, by no means all organs fall asleep: while one of their parts, the most tired, falls into sleep, the second, less tired, continues to stay awake. The answer to the question "Why do I have dreams?" It is quite obvious: dreams with dreams are precisely because some organs have already fallen asleep, while others continue to be awake for some time. But gradually they calm down, as a result of which a calm and deep sleep sets in.
However, nerve diseases and other ailments can cause loss of sleep, insomnia, improper wakefulness, or, conversely, a deep and rather heavy sleep, a kind of hibernation, and in some cases even lethargy. Any dreams are the result of the activity of memory and developed imagination, which are free from the participation of other feelings and abilities. That is why there are dreams that are so different in meaning, but have much in common with what may very well happen in reality. So, for example, in people who are sick or engaged in excessive, overwork, dreams are often terrible and difficult. When one of the vital organs is irritated, overworked or sick, sleep is often restless, and light sensations at this moment become extremely powerful. For example, the noise of a car passing outside a window can be regarded as peals of thunder or a gunshot; mosquito bite - like a bite of a scorpion or a huge snake.
Have you ever wondered why there are dreams that in their sense almost always correspond to mental development, social status, physical condition, age, and temperament of a sleeping person? After all, the rich dream mostly of luxury and pleasure; the poor - need, labor, requests, humiliation; the actor dreams of a stage, a standing ovation, an audience; to the patient - doctors, hospital, drugs, etc. Also, the dreams of the poet or artist will never be dreamed of by the craftsman, and the beggar is unlikely to see the dreams of the oligarch. In other words, who “breathes” with what is what he dreams of, for the cosmonaut is not always surely aware of the subtleties of the production of chemical reagents.
Many are interested in the question of what dreams dream of. Yes, it is likely that in some cases dreams can actually show pictures from the past or predict the future. But if you do not consider them as something mystical, then any bright, good or bad dreams are caused by certain reasons. It can be strong impressions received in the waking state, due to any out of the ordinary incident or event, as well as personal participation in a particular extraordinary incident. And they can also be caused by poor stomach condition or overeating at night, an uncomfortable bed, or an uncomfortable body position during sleep. Based on this, it can be noted that very few dreams have real, prophetic significance.
In addition, despite the fact that a person sees dreams every night, he can not always remember them in the morning. If he can remember something, then these are only small fragments of the very last, morning sleep, which a person sees before his awakening. Be that as it may, the human brain is still not fully understood, and why dreams are actually dreaming of what is behind them - so far it remains a curious and unresolved mystery.