‘Terrifying’ sleep paralysis reality as sleep scientist weighs in

Almost one million in the UK are losing sleep to terrifying episodes described as “sleep paralysis demons”, as the phenomenon explodes across TikTok and UK search engines.

New research from Hillarys revealed that a small portion of Brits experience frightening night-time hallucinations that are the main reason they are struggling to sleep.

Google searches for ‘what is sleep paralysis demon’ have surged by 5,000% in the past month alone, while TikTok engagement around the trend continues to climb rapidly.

Tom Coleman, sleep scientist at Hillarys, on how ‘sleep paralysis’ occurs:

“When we dream, we are typically in REM (Rapid Eye Movement) sleep. During REM sleep, the brain becomes highly active. REM sleep is known as paradoxical sleep because the brain is almost as active as when we are awake and during REM vivid dreaming occurs.

At the same time, the brain switches off most voluntary muscle activity, this is called REM atonia. It is a protective mechanism that prevents us from physically acting out our dreams, so if you’re dreaming that you are running or fighting, your body remains still. Normally, when REM sleep ends, muscle tone returns and we either move into another sleep stage or wake up fully.

Sleep paralysis occurs when this process becomes ‘uncoupled’. The brain wakes up, but the body remains temporarily in REM paralysis, and this is known as a REM–wake dissociation.

During this state, a person may be conscious, aware of their surroundings, yet unable to move, and still partially dreaming because REM dreaming is still active and dream imagery can intrude into waking awareness. This is why hallucinations occur.”

SleepTok: From niche experience to viral phenomenon

On TikTok, the trend shows no signs of slowing. The hashtag #SleepParalysisDemon has generated search popularity of more than 1.1 million in the past six months, with a sharp spike this month. In just the last seven days, searches have jumped by 31%, reaching nearly 300,000 (291,000).

Content ranges from hard-hitting first-person accounts describing shadowy figures, pressure on the chest and an inability to move, to dark humour and memes about ‘the demon at the end of the bed’. What was once a rarely discussed sleep disorder has become a fast-growing online conversation – particularly among younger users.

Tom Coleman explains how scary the sensation can become:

“Hallucinations during sleep paralysis are often intense and threatening, some people may sense an intruder, see shadow figures, feel pressure on their chest, or believe someone is in the room. Although it feels terrifying, breathing continues normally. The sensation of chest pressure happens because the skeletal chest muscles are relaxed while the diaphragm continues to function.

Episodes usually last from a few seconds to a couple of minutes, though they can feel much longer because when we dream, we have no sense of time.

Common triggers can include sleep deprivation, irregular sleep schedules, jet lag, shift work, high stress or anxiety and in some cases, narcolepsy. It is more common in students and individuals with disrupted sleep patterns. While frightening, sleep paralysis is not dangerous. Improving sleep regularity and reducing stress significantly lowers the likelihood of episodes.”

A terrifying real-life experience

For Melissa Austin, 28, from Worcestershire, the experience is far from a social media trend:

“I woke up but couldn’t move. My entire body felt frozen – I didn’t know if I was asleep or awake. At the end of the bed there was this absolutely huge, black mass just standing there.

It didn’t feel like a dream. It felt real. Then it started climbing onto the bed and pinning me down. I tried to scream but nothing came out. I truly believe I felt what I can only describe as breath on my face from this thing.

The first time it happened I was 16. I didn’t have the words for it. I told my mum and she said I’d probably just had a bad dream. I knew it wasn’t that. Since then, it’s happened numerous times – always at times where I guess I’m slightly more stressed than usual – which isn’t abnormal since I gave birth to my first child.

When sleep paralysis started appearing all over TikTok, I thought maybe people would finally get it. But it’s all ‘shadow man’ filters and memes. People think it’s cool or spooky but it really isn’t. It’s genuinely terrifying, and it makes it harder for me to talk about because now when I bring it up, people think I’m being dramatic or jumping on a trend.”

Even now, I sometimes dread going to sleep when I’m stressed because I don’t know if it’s going to happen again.”

Melissa’s account reflects the classic symptoms of sleep paralysis: temporary immobility when falling asleep or waking, often accompanied by vivid hallucinations that can feel intensely real.

With almost one million UK workers potentially affected, sleep paralysis is no longer just an obscure medical term – it is a workplace wellbeing issue intersecting with viral online culture.