Why do some dreams wake up and remember some at all?

Our sleep is divided into several stages, the appearance of dreams is generally in the REM period, dreams generally last about an hour, in the time of about 8 hours from when we enter sleep to wake up, we will repeat about 3-4 sleep stages, each sleep stage will have dreams, that is to say, we will have several dreams in one night, but not every dream we can remember. There are even many times when we wake up and feel like we have no dreams all night, and the reason for this is that we are in REM at the time of the dream, and if we wake up during this period, we will remember the content of the dream we did, otherwise it wouldn't.

When you sleep, brain waves alternate between fast and slow waves

Fast waves belong to deep sleep and are prone to dreaming.

Slow waves are light sleep, which is easy to forget.

So when you wake up in the midst of a fast wave, you remember, and vice versa

Sleep is indeed divided into fast and slow waves, but slow waves generally do not dream, fast waves do. Generally, the memory of dreams is relatively shallow, and because it is in the subconscious range, it is actually the thoughts that are usually suppressed by you, out of self-protection, the brain generally does not let you remember, so the memory of the first few dreams you have during sleep will be covered up later, and when you wake up, you only remember the last dream.

Scientists have shown that if a person wakes up within 5 minutes after dreaming, the person's memory of the dream is relatively clear, on the contrary, if you wake up more than 5 minutes, the dream will be very blurry or even completely forgotten.

Maybe you think that there is more than 5 minutes of time, it is because people's perception of time in the process of sleep is very wrong.

To put it simply, some dreams are deep and some are shallow, and the consciousness level is shallow, and the shallow ones remember how much and deep remember less, for details, please refer to Freud's theory.

Because forgetting dreams is a natural process.

The causes of dreams are known to have both psychological and physical causes, but even in these two aspects, human beings are still unable to explain the mechanism of dream formation.

The events and shouting scenes formed in the dream come from people's existing cognition and memory, which contains the contents of sight, hearing, smell, taste, touch, feeling, etc.

China is the country where Zheng Kai has studied dreams for the first time, and as early as Freud more than 2,000 years ago, we had a monograph on dreams - "Zhou Gong's Interpretation of Dreams".

However, the interpretation of dreams in "Zhou Gong's Dream Interpretation" is not carried out from the scientific angle of scum.

Based on the social and technical conditions of the time, the interpretation of dreams in this book has considerable historical limitations.

5. The cerebral cortex is the main area responsible for memory, and the function of the cerebral cortex will also be affected by the hormone of the body: during sleep, the norepinephrine in the cortex will be reduced, resulting in inattention, which will form some fragmentary thinking and memory, which is not easy to remember.

When you think about it, we often only remember the full story, but not the name of the main character.

6. Dreaming also has an adaptive function, which can make people better adapt to the environment instead of being eliminated by the environment.

So dreaming actually has a variety of functions, for example, to strengthen our memory, to reorganize the information we have obtained, to fulfill our heart's desires, and so on. At the same time, in order to allow people to clearly distinguish between dreams and reality, and not to become mentally ill.