10 Terrifying Things That Can Happen To You Whilst Sleeping

For many sleepers, moving in the night is not an uncommon thing. Rolling over or the occasional twitch is nothing to be worried about and is part of the normality of a sleeping pattern as the brain moves from deep sleep to a more awake state and back again.

Periodic Limb Movement Disorder/ PLMD is a more extreme version of the experience most people have during the night. It is a sleep disorder in which the sufferer will involuntarily move their limbs or jerk them as they sleep. It is not the same as restless leg syndrome, which is the willing urge to move the legs due to discomfort.

PLMD usually occurs in the lower part of someone's body, and can be a symptom of regular hypnagogic jerks. They cluster in 20-40 second episodes and can occur all the way through the night. It is not considered medically serious, unless the sufferer is waking to pain because of the twitching that has occurred.

PLMD is usually a secluded movement in small sections of the body such as the hand, ankle or feet.