Ever find yourself momentarily paralysed as you’re falling asleep or just waking up? It’s a phenomenon that goes by the name of sleep paralysis; and while it can be a once-in-a-lifetime experience for some, for others it can be a frequent, even nightly, occurrence that causes intense fear.

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While the word ‘terrifying’ springs to mind, it may bring some comfort to know that sleep paralysis – a form of parasomnia – isn’t perilous, nor does it usually signify an underlying serious condition.

We asked Dr Nerina Ramlakhan, Silentnight sleep expert, for the facts…

What exactly is sleep paralysis?

“Sleep paralysis occurs when the body goes into a state of paralysis, while we dream. It's normal for your muscles to be paralysed at certain times when you're asleep.

"However, sleep paralysis occurs when the mechanism that causes your muscles to relax during sleep temporarily persists after you've woken up, which leaves you unable to speak or move and, in some cases, causes disturbing hallucinations and a sense of dread.

"This can be very frightening for some, and can last from a few seconds to several minutes.”

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What causes sleep paralysis?

“Sleep paralysis tends to be caused by underlying neurological reasons, but can be exacerbated by poor lifestyle habits, including too much caffeine and alcohol, and sleep deprivation.

"Using a Smartphone or tablet around bedtime can also be a factor, as this can over-stimulate the nervous system.”

Who can develop sleep paralysis?

“It can happen to anyone; although age can be a factor, and sleep paralysis tends to be more common in teenagers and adults.”

How is this phenomenon diagnosed?

“A polysomnography, also called a sleep study, is a test used to diagnose sleep disorders, including sleep paralysis.”

Is sleep paralysis treatable?

“The symptoms of sleep paralysis can often be improved by altering your sleep habits and creating a restful sleeping environment.

"Sleep paralysis often affects people who are sleep deprived, so ensuring you get enough sleep may reduce the number of episodes you have.

"Most adults need six to eight hours of good quality sleep each night. If sleep paralysis persists, medical professionals can prescribe medication to help relax the nervous system.”