Sleep paralysis may happen to you once in your lifetime or it may happen frequently. You wake up and realize that you are unable to move. A disruption in REM sleep is believed to be the culprit of sleep paralysis because the body goes into a stage of muscle atonia, or weakness, which keeps the body from acting out our dreams. Sleep paralysis can occur as we are waking or at the onset of sleep and is often associated with horrifying visions such as that of an intruder.
