In the first edition of his book Sacks explicitly rejected the diagnosis of ‘hysterical paralysis’ as it was then understood, although he approached this diagnosis more closely in subsequent revisions ...

Sleep is a time of rest and relaxation, but there are actually some vital bodily functions that your body simply cannot do ...

Many people who experience sleep paralysis see frightening hallucinations some call "sleep paralysis demons." - Illustration by Leah Abucayan/Alberto Mier/CNN ...

"This type of hallucination is a hallmark for many people with sleep paralysis.It occurs during transitions into or out of rapid eye movement, or REM, sleep, similar to a traffic jam at a busy ...