Sometimes, when you are half awake from your sleep, you noticed that you cannot move your body or make any sound. Thus you begin to recall something about being haunted by a ghost, thinking that there is a ghost lying on top of you causing you to be immobilized. 

As a matter of fact, this phenomenon has nothing to do with ghosts. Experts call this phenomenon as sleep paralysis. So what is it all about and why does it happen?

How can sleep paralysis happen?

This phenomenon usually occurs during the REM (Rapid Eye Movement) stage of sleep. At this time, in order to prevent our bodies from taking actions that would hurt ourselves or respond to dreams, our Voluntary Muscles will be in a "paralyzed" state. This is why we cannot move.

Sleep paralysis happens when our brains are awake during the REM stage, but our bodies are still immobile. When people experience sleep paralysis, they will have hallucinations due to fear. This also explains why some people said that they saw "ghosts" and "demons" appearing in the room, and heard footsteps slowly approaching.

Why do you experience sleep paralysis?

There is no absolute cause of sleep paralysis. But, people with stress, irregular schedules, insufficient sleep, anxiety or depression would have a higher chance of having sleep paralysis. 

If you have experienced sleep paralysis, don't feel scared because each sleep paralysis normally lasts only a few seconds to several minutes. Don't worry about whether you will experience this phenomenon again before going to bed because excessive anxiety will most probably increase the chance of it happening again.

It is normal to experience one or two times of sleep paralysis for a long time, but if this phenomenon continues to occur repeatedly, you must adjust your sleeping state, rest schedule, and mental state.