They know no boundaries between young and old, rich and poor, races, religions and nationalities. In all cultures we find some version of «counting sheep» before making a decision.
Old cultures thought that dreams were messages from the gods or from the dead and that they had important messages as predictions of the future.
This question is still an unknown but there are things that we can know.
When we sleep we go through several stages, the dreams happen mainly during the phase of rapid eye movements called REM (Rapid Eye Movement), when you are at this stage to avoid hurting all our muscles are disconnected and there is almost total muscle relaxation, and a mental activity similar to the one we have when we are awake, if you wake up at this stage (REM) you will most likely remember that dream.
While we sleep, the body enters the state of anabolic reaction during which functions of construction and repair of organs and tissues such as muscles and bones are carried out, as well as the supply of the immune system.
Studies show that sleep plays a fundamental role in the formation of long-term memory, that is, during the night it is when the learning of what we live during our day is formed.
They also have a much higher risk of cardiovascular disease, cancer, diabetes and depression.
Although the exact mechanism has not been discovered, a hypothesis has been created that dreams are a way to maintain mental activity while performing all those repair processes in our brain.
All mammals dream, have you noticed it in your dog?, so do many birds and even reptiles.
Freud maintains that all dreams represent the realization of a wish on the part of the dreamer, even nightmare dreams. There are negative dreams of desires, where what appears is the breach of a desire. For this several explanations are given, among which is the satisfaction of a masochistic tendency. Nevertheless, Freud's general conclusion remains: dreams are realizations disguised as repressed desires. According to his theory, the "censorship" of dreams produces a distortion of their content. So what may seem to be a set of dreamed-out images without meaning can, through analysis and the "deciphering" method, be shown to be a set of coherent ideas. Freud proposes that the value of the analysis of dreams lies in the revelation of the subconscious activity of the mind.
Freud's theory of dream interpretation represents the first theories of this in relation to the nature of the psychology of unconscious dreams, the importance of childhood experiences, the "hieroglyphic" language of dreams and the method that the called "psychoanalysis"
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For example, if you hate someone in specific and he always wears red, you may dream that you always kick a monster dressed in red, so you relieve tension and you will not feel guilty for wanting to hit the person who you hate
Freud warned that symbols are not universal, if not personal, each person should interpret them according to their circumstances and not resort to those easy dictionaries of dreams.
He carried out studies in which he asks a group of students to focus on a problem before going to sleep and upon awakening half of them found the solution.
There are many examples of scientists, mathematicians, artists and philosophers who have dreamed of ideas that have changed the world.
For example:
