What causes sleep paralysis and how do you come out of it?

Sleep cycle broken: During delta sleep, a restorative part of sleep,cycle, every muscle group in the body is,paralyzed except the eyes and diaphragm. If our wake/sleep cycle does not function correctly, we can become consciously awake, moving our eyes and breathing, but remaining paralyzed for a time.

Sleep Paralysis: Sleep researchers conclude that, in most cases, sleep paralysis is simply a sign that your body is not moving smoothly through the stages of sleep. Rarely is sleep paralysis linked to deep underlying psychiatric problems. http://www.webmd.com/sleep-disorders/guide/sleep-paralysis#1