In a dream, our body continues to act. During this natural process, scientists directly distinguish sleep and dreaming, visions (or hallucinations), dreams. We will deal with terminology later. Initially, it should be mentioned that all types of dreams represent the correspondence of spiritual phenomena, which in the aggregate allegorical form can explain the future and past of a person.
The main types of sleep
The following types of it are distinguished:
- daily periodic;
- seasonal periodic (hibernation of some animals);
- narcotic;
- hypnotic;
- pathological.
Types of sleep and their characteristics
In addition to the main varieties, there are still natural and artificial. They are considered as the main two types of sleep. The natural process most often occurs both in humans and in animals unexpectedly, without any extraneous influences. The artificial appearance is caused by various factors and influences (electrosleep, narcotic, hypnotic).
The natural forms of sleep of a healthy adult and most mammals have an inherent frequency. However, the frequency and alternation may vary. An adult generally sleeps at night, and is awake during the day. This periodicity is called monophasic. There are people who rest twice a day - the main dream at night and an additional day. This is a two-phase periodicity. Most mammals use polyphase types of dreams: they are able to fall asleep and wake up several times during the night and day, without the need for strict observance of alternating periods of rest and wakefulness. Children also have a polyphase sleep pattern . This can be seen in the example of newborns who are in this physiological state most of the time. However, it is interrupted several times a day due to natural needs, but then, due to the influence of upbringing and the environment, the sleep rhythm begins to be rebuilt, approaching the same in an adult.
Artificial types of sleep can be regulated by dosing the influence of factors that cause them (sleeping pills, electric current, etc.).
The length of the periodicity of natural sleep in different animals is very variable, and even in individuals of the same species it differs sharply at different times of the year.
Scientists show great interest in the so-called seasonal hibernation of animals. Zoologists investigate its causes and physiology.
The classification of natural dreams
Natural are those types of dreams that a healthy person is able to see from time to time:
- healthy (restores reality by some signs);
- vision (restores a picture to an awakened person that he already saw in a dream);
- predictive sleep (includes some warning);
- dreams (embody in dreams that which made a strong impression on a person in reality);
- ghostly night visions (the repeated appearance in a dream of certain images; most often this happens with children and people in old age).
Among all of the above, only the first three types of sleep deserve special attention, since the last two in most cases lead to misconceptions.
Pathological sleep
According to its etiology, this condition in the process of its manifestation is divided by scientists into a number of varieties. It occurs exclusively during anemia of the brain, when it receives insufficient blood supply; in the presence of high pressure, when tumors develop in both hemispheres or if the brain stem is affected in some areas. Often, pathological sleep patterns can occur for many days, and this can last up to several years. This condition is changeable, accompanied by both reduced muscle tone and increased.
Pathological dreams are often confused with hypnotic states, but they are not the same thing. Hypnosis can be caused by special environmental influences or certain actions of a person who inspires another with a particular need for a sleep phase. During the pathological variety of the physiological state, cortical voluntary activity is turned off. In this case, partial contact with others and the presence of sensorimotor activity is maintained. The nervous system during this dream can be both in a depressed inhibited state and in an excited state.
Intermittent daily sleep
As mentioned earlier, in a healthy person there are 3 types of dreams: monophasic (once a day), diphasic (twice), and in infancy - also polyphase.
The newborn generally spends about 21 hours in the dream phase; a child aged from six months to 12 months a day sleeps for 14 hours, up to 5 years - 12 hours, from 5-10 years - about 10 hours. An adult sleeps on average 7-9 hours a day. At an older age, the duration of sleep decreases slightly.
Lack of sleep
A prolonged lack of proper rest (from 3-5 days) is characterized by the occurrence of mental disorders. Arbitrarily irresistible craving for sleep begins: to prevent its onset only through strong painful irritations - pricks with needles or electric shocks. In a person deprived of sleep, a decrease in the rate of reactions is pronounced, during brain work fatigue increases and the accuracy of operations decreases.
With prolonged insomnia, changes in vegetative functions are not so noticeable. They are manifested only by a slight decrease in body temperature and a slight slowdown of the pulse. But not every person experiences mild physiological and psychological changes, with 40-80-hour insomnia, the consequences can be more severe.
Narcotic dream
Narcotic forms of sleep manifest themselves in the form of a temporary loss of consciousness. There is inhibition of reflexes with a complete decrease in muscle tone. A person deepens into this state with the help of anesthesia, which affects the central nervous system.
During immersion of the patient in anesthesia, the functioning of the medulla oblongata continues, since in its area there are life-supporting centers - vasomotor and respiratory. If the effect of narcotic substances lasts for a long time, then a deepening of the described condition may occur, as a result of which paralysis of these centers is recorded. Long narcotic sleep leads to the death of the patient.
Hypnotic dream
The discussion of what types of dreams are, we continue with a more detailed description of hypnotic sleep. This condition is not fully understood until now. It is not known what causes the phase of dreams itself. During the onset of this condition, significant physiological changes occur in the processes of the central and autonomic nervous systems, as well as other organs and systems of the human body.
Seasonal intermittent sleep
These types of dreams are also known as hibernation, numbness, or deep sleep. This type of condition is characterized by a significant decrease in body temperature, while energy costs and the intensity of each physiological process are reduced. Hibernation is characteristic only for some species of animals.
Animals that are able to maintain body temperature due to internal heat production are called endothermic. There are also ectothermic organisms called cold-blooded. Man is warm-blooded, which means that he treats endotherms in the same way as mammals with birds. That is why people cannot hibernate; their body temperature does not allow them to withstand prolonged sleep. But there are warm-blooded ones who still fall into seasonal sleep, they are called heterothermal endotherms.