1. Sleep paralysis
Phenomenon: we wake up at night without being able to move. This can be accompanied by hallucinations and the impression that a person is watching us. In ancient times, this phenomenon was attributed to demonic forces.
Explanation: In general, when we sleep, our brain “paralyzes” so that we do not move too much during sleep. Sleep paralysis occurs when our muscles are still “blocked” while the brain is awake.
About 7% of the world’s population has experienced this phenomenon at least once in their lifetime (source). It seems that this happens more often when you sleep on your back.
2. Hypnotic Hallucinations
Phenomenon: when one is between the waking and the sleep, one sees images in front of one’s eyes that one can not control. They are often scary faces or fantastic creatures.
Explanation: This is one of the rare forms of hallucination that affects sane individuals. In general, they are more about children (source), which explains why they can not sleep. They often occur because of stress or a fertile imagination. It can also happen when you fall asleep while drunk.
3. Speaking while sleeping
Phenomenon: In general, the person who suffers from somniloquy does not even realize it. This phenomenon is totally harmless from a psychological point of view. The only drawback would be to reveal a secret involuntarily.
Explanation: In general, this disorder is observed in men and children (source). The main cause is stress. The subconscious of the individual tries to fight against something that disturbs him in reality.
4. Nested Dreams
Phenomenon: the person dreams of something, then “wakes up” and continues to live strange events. In reality, she just dreamed that she was waking up, but she is still asleep. The film Inception is based on this phenomenon. And since its release, many people claim to have lived.
Explanation: Some mystics claim that the individuals who experienced it have predispositions to the practice of spiritualism. But science has not yet elucidated this mystery.
Phenomenon: this disorder is the opposite of paralysis of sleep: your consciousness is asleep, but your muscles are moving. Sleepwalkers can walk, do simple things and even walk out of their homes, which can be dangerous. In the morning, they do not remember anything.
Explanation: Sleepwalking affects 5 to 10% of the population, and again, it mainly affects children (source). The cause of this phenomenon remains unknown, as are the means of treating it.
6. Head syndrome that explodes
Phenomenon: the person wakes up like after an explosion or a loud noise. Sometimes she is even sounded by the power of the noise she thinks she has heard. This can be accompanied by a ringing in the ears or flashes in front of the eyes. The phenomenon is not dangerous, but it can be scary. Some think it’s a stroke.
Explanation: For some unknown reason, the neurons responsible for sound processing are activated in the brain (source). Sometimes the phenomenon is due to insomnia or jet lag after a long trip.
7. Sleep apnea
Phenomenon: sleep apnea is the stop of breathing during sleep. It usually causes awakening. The quality of sleep is reduced, the brain feels the lack of oxygen and it is difficult to go back to sleep properly. During these “seizures”, blood pressure changes, which can lead to heart problems.
Explanation: During sleep, the throat muscles relax, and in some people this causes airway obstruction. Subjects at risk are overweight individuals, smokers and the elderly. Unusual fact: playing the didgeridoo (aboriginal musical instrument of Australia) helps fight sleep apnea (source).
8. Recurring dreams
Phenomenon: we make the same strange dream several times.
Explanation: Psychologists think that the brain tries through these dreams to draw our attention to things we are not aware of. These dreams are repeated as long as the situation is not resolved (source).
9. Falling out of bed
Phenomenon: it sometimes feels like “falling” in bed, causing a wake up awake. Sometimes we dream beforehand that we are flying, then we fall; this feeling is quite unpleasant.
Explanation: sleep is like death. The breathing and the heart rate slow down, the muscles relax completely. Then the brain “gets scared”, he thinks it can be death and he “verifies” that the body is still alive by sending an impulse to the muscles.
10. “Body Exit” Experiences
Phenomenon: it is a neuro-psychological phenomenon where the person, who is in a state between waking and sleeping, sees himself from an “outside” point of view. The mystics consider it as a proof of the existence of the soul.
Explanation: this phenomenon is difficult to study. To this day, scientists know that the illusion of “body exit” really exists, but they do not know how it works or why it occurs. They do not know how to prevent it either. Some people seek to voluntarily enter this state, in order to broaden their perception of the world.
11. Illumination during sleep
Phenomenon: it happens that we spend days on a problem without being able to solve it, and suddenly our brain gives us the solution during the night. The important thing is to remember when you wake up.
Dmitri Mendeleyev gave us an example: he had a hard time building his periodic table, and one night he would have seen it in a dream. A similar phenomenon would have happened to the chemist Kekule, who would have dreamed of the formula of benzene.
Explanation: sometimes our subconscious already knows the answer to a question, but we are not yet aware of it. That’s why he communicates it to us through dreams. The brain sometimes gives us pleasant surprises, does not it?