Most likely you’ve experienced a sudden strange sensation of falling when going to sleep, which rudely awakens you. In reality it is not a dream of falling, which happens in deep sleep, but an instant physical sensation that wakes us and is accompanied by a hallucination, not a dream.
To better understand this phenomenon, it is necessary to understand the mechanism of sleep.
Dream begins in a part of the brain called reticular formation, which sends signals to the spinal cord to relax the muscles and suppress stimuli. The jerk that you feel when you wake up does not wake you when you have already fallen asleep, because the body absorbs its own consciousness. Everyone agrees with this. But then the scientists’ opinions differ. Here are 3 possible explanations of this phenomenon:
1. The signal moved in the wrong direction
A research group noticed that the signal from the reticular formation switches in some people. Rather than suppressing the contraction of the muscles, it enhances their response to almost any stimulus. In science, it is termed “hypnic jerk”. When people experience it, the sudden change of the body position without direct support under the arms or legs can make a person believe that the experienced feeling was caused by a fall.
2. The body is relaxed, while the brain is still working
Other scientists consider that the falling sensation comes from the very relaxation, especially if the person is concerned and cannot get comfortable. As soon as the muscles relax during sleep, the brain remains awake, watching the situation. Flaccidity of the muscles is interpreted by the brain as a feeling of falling, which makes it try to wake the person.
3. Stress caused hallucinations
Contrary to what many people think, hallucinations are not something out of the ordinary, and many of us in one way or another have experienced them. Hallucination is just an experience in which the brain incorrectly interprets some group stimuli. For example, you may suddenly feel like seeing a cat’s eye watching over you, and it turns out that this is actually a pile of garbage near a column. The brain just makes a hasty conclusion and creates an image that is not quite true.
Such hallucinations are enhanced by stress, when the brain is rapidly making hasty conclusions, and fatigue when the brain does not handle as much information as it does under normal conditions. When you fall asleep being concerned about something, you are hypersensitive to stimuli, and the uncomfortable situation leads to the fact that the brain receives a sudden signal about the danger (the body is falling), and tries to find the reason why it is happening. It creates drowsiness, in which we experience this weird feeling.