Sleep paralysis is a condition that occurs when an individual is unaware that he or she is actually in a “dream”. In fact, the body moves into REM sleep, which is believed to be the deepest phase of sleep.
A series of rapid eye movements and dream-like images appear during this stage of sleep, and some patients experience extreme, abnormal fear at this time.
In turn, the brain triggers a state of paralysis and causes the person to experience some form of fear-induced paralysis.There are certain reasons why this occurs.
Read more on themindsjournal.com