This may be the scariest thing you ever read on SamadiMD. There is a condition called Sleep Paralysis. No this is not insomnia or sleep apnea, this is a condition or phenomenon that occurs either when falling asleep or being awakened. It's thought to be a mix-up of normal REM sleep (the deepest sleep we achieve throughout the night.) People who experience it are in some sense conscious and aware that they're aware they're in bed for example. But some part of their body believes they're still asleep, in particular their muscles. The muscles become paralyzed, something that happens in REM sleep. Some scientists believe this is an evolutionary mechanism that prevents people from acting out their dreams.
However, when sleep paralysis occurs, this what's often known as a normal function becomes terrifying. The experience is often accompanied by some kind of hallucination, usually something scary. Patient's have reported feeling as if they're being pinned down by a huge weight on their chest. Recently a psychologist from Washington State University published a book on the condition where author Brian Sharpless argues the phenomenon may offer up naturalistic explanations for night terrors and also nighttime phenomena found in folklore all over the world.
The core experiences are similar, even though every culture brings its own twist to it. It's paralysis. Everything but the eyes is frozen; this leads to a conscious awareness during it.
This is what makes it incredibly frightening for people.
In a 2011 study of 35 previous studies, Sharples combined a sample size of more than 36,000 people and found about 8% of the population. It's still not quite clear how many people suffer from this.