The ancients believed that there was always a reason for dreaming. Wang Fu once said: "If people dream strangely, they will gain more and accomplish nothing less." He thinks there is always a reason for dreaming.
There are psychological and physiological reasons for dreaming, but even in these two aspects, human beings still can't explain the formation mechanism of dreams.
The events and scenes formed in dreams come from people's existing cognition and memory, including sight, hearing, smell, taste, touch and feeling.
All these elements that appear in people's dreams are based on memory.
The origin of dreams
Dream is an image language.
"Zhuangzi's Theory of Everything" said: "Sleeping is a big dream."
These images range from ordinary things to surreal things; In fact, dreams often inspire art and other aspects. German chemist Kekule claimed to dream that a snake was swallowing its own tail and realized the molecular structure of benzene ring.
Generation of dreams: when people sleep, brain cells also enter a state of relaxation and rest, but some brain cells are not completely rested, and weak stimulation will cause their activities, thus triggering dreams.
For example, there is something that makes you particularly excited during the day, and you are still thinking about it before going to bed. When other nerve cells in the brain are at rest and these nerve cells are still excited, you will have a dream with similar content, which is called "thinking day and night".
Most scientists believe that all human beings dream and sleep at the same frequency every time.
Scientific explanation:
The cause and purpose of dreams are still inconclusive in academic circles. It is generally believed that dreams are caused by some nerve impulses released by the brain when processing information and consolidating long-term memory (such as dust raised during cleaning or information flow being processed), which are interpreted by conscious brains as bizarre vision and hearing.
First of all, Hobson and McCarley put forward the theory of "activation-synthesis" in 1977: the pons in the brain stem will constantly send out signals (PGO waves) to stimulate and activate the conscious part of the brain and make it synthesize a meaningful dream.
However, Solms later found that patients with brain stem injury still dream, while patients with parietal lobe injury (parietal cortex responsible for body sensation and sensory integration) do not dream. Perhaps the brain stem is only related to REM dreams, while the parietal lobe is related to REM dreams and NREM dreams.
In 2004, Zhang Jie put forward the theory of "continuous activation": one of the functions of sleep is to transform temporary memory into long-term memory, and REM stage deals with unconscious "procedural memory" instead of conscious "declarative memory" in eye movement (NREM) stage.
In the REM stage, the unconscious part of the brain is processing programmed memory, while the activity of the conscious part is reduced to a minimum because the sense is cut off. At this time, the information pulse from the memory bank will activate the conscious part and let it weave a dream through association.
When another pulse came, I had another dream, and the dream suddenly changed.
Others think that the reason or function of dreams is:
(1) Through random mutation, new ideas and strategies are generated by "Darwin process";
(2) clear the garbage in the brain. Dreams are the last glimpse of garbage;
(3) The continuous stimulation of long-term memory, the strangeness of dreams during sleep comes from the storage format of long-term memory, but the awake brain can give it a correct explanation;
(4) Connecting distant but related memories and strengthening them into a story;
(5) transforming external stimuli into dreams to prevent them from being awakened;
(6) Self-satisfaction, reducing psychological pressure;
(7) supplying oxygen to the cornea through eye movements, and so on.
However, some people in Taiwan Province Province put forward a "psychosomatic theory" of dreams: when dreaming, fantasy and self are separated, and people will not notice that they are dreaming.
"Fantasy" obtains data from sensory memory and then sends it back to the sensory area to become illusion. The purpose is to use simulated sensory signals instead of real signals to drive autonomic nerves to perform psychosomatic functions.
Pain and pressure will drive the "repair nerve" in the autonomic nerve, and the repair nerve will be arranged into many meridians, which will have a chain reaction in the brain and spine. One of the functions of dreaming is to simulate the extremely dense signals of sports massage, and drive the meridians to repair the body when the growth hormone rises.