The definition of sleep paralysis describes a transient state in which a person is awake but feels unable to move, speak, or scream, as if frozen in place. These sensations may or may not be accompanied by visual and auditory hallucinations, or oppressive sensations and images of a threatening presence (shadows, dark masses, buzzing sounds).
Sleep paralysis always occurs during the REM sleep phase, when brain activity is particularly intense.
Halfway between wakefulness and sleep, this sleep disorder belongs to the category of parasomnias. It's estimated that around one in five people experience it at some point in their lives, with some experiencing it repeatedly.




