There is a place just behind the eyelids where reality thins. It happens in the stillness of night, often in silence, when the body sleeps but the mind stirs with a peculiar awareness. This is the threshold of sleep paralysis — a state both terrifying and profound.
Science defines sleep paralysis as a glitch in the REM phase. During this stage, the body remains paralysed as it does in dreams, but the brain wakes up before the paralysis ends. People report being unable to move, breathe, or speak. Some feel a heavy presence, others see a dark figure at the edge of the bed. These are dismissed by neurology as hallucinations — real-feeling projections of a brain in sensory confusion. But despite studies and theories, science admits it cannot fully explain why these hallucinations are so uniform, so ancient, so universally feared. Why do so many people, from such different cultures, see “the same thing”?
In recent years, Dr. Baland Jalal, a neuroscientist affiliated with Harvard and Cambridge, has been at the forefront of trying to understand this phenomenon. His research explores not only the biological mechanism of sleep paralysis but also its emotional and cultural depth. Jalal developed a method called Meditation-Relaxation (MR) Therapy, designed to help people reduce the frequency and fear of episodes. In his pilot study with patients — some suffering from narcolepsy — MR Therapy reduced the frequency of episodes by half and significantly lowered anxiety levels. Remarkably, this effect occurred even though the hallucinations themselves did not disappear.
Jalal argues that what science explains as REM intrusion may, in subjective experience, feel like an encounter with the spiritual. “It’s a spiritual experience in a scientific wrapper,” he has said. His work affirms that while we can study the brain’s behaviour during these events, we still cannot fully grasp why these particular images — demons, shadows, dark figures — appear so consistently and powerfully across time and cultures.
As CNN Health reported in June 2025, sleep paralysis affects a surprising number of people — about 8% of the population globally, according to meta-analyses. For some, it occurs only once or twice in life. But for others, it’s recurrent and traumatic, associated not just with immobility, but with overwhelming fear, hallucinations, and even a sense of death.
The article describes what many know from personal experience, including a dark figure, a heavy weight on the chest, whispers, and the feeling of being watched. People have called it “a demon,” “a ghost,” or “the devil sitting on my chest.” This isn’t new. Cultures from Mexico to Nigeria to Japan have words for it. In Samoan terms, some would say this is an aitu — a spirit, often feared or unsettled.
CNN also referenced Jalal’s Meditation-Relaxation Therapy, which teaches sufferers to reinterpret the experience in real time. Instead of fighting or fleeing, they are encouraged to focus inward, stay calm, and remind themselves that the episode is only temporary. For some, this reduces the panic and breaks the loop. But even Jalal’s research does not attempt to explain why the paralysis demon appears at all — only how to cope with it.
Interestingly, the article acknowledges that even when the body is still, the emotional brain remains highly active. The amygdala — responsible for fear — fires during sleep paralysis, and without physical input from the senses, the brain fills in the blanks. That’s the scientific view. But what if those blanks are filled not randomly, but with something that already lives in the margins of consciousness — something ancestral, spiritual, or real?
Across the Pacific, and particularly in Samoan, Tongan, Fijian, and Hawaiian traditions, sleep is understood not merely as rest, but as travel. The spirit — agaga, laumālie, uhane — leaves the body to roam. It visits loved ones, wanders the past, flies over lands it once knew. But it must return. And some say it can get lost.
Many remember dreams where they flew over their villages, over rooftops and trees, feeling the wind of home in a way waking life cannot offer. But not all dreams are free flight. Some are traps. Places of damp, oppressive dark. A feeling of being stuck in-between. Of seeing too much. Of knowing you are asleep but feeling deeply that something else is there — watching, waiting.
This darkness is not metaphorical. It is remembered vividly, sometimes from childhood. It’s a texture, a pressure, a presence. Those who have touched it describe a kind of existential gravity, as if reality itself was bending under the weight of something unseen but real.
For those who believe in the spirit’s nightly voyage, this makes sense. When you fly, you risk drifting too far. And if the path back is blocked — by fear, by a covered foot, by forgotten prayers — you might not return. Many cultures believe this is how some people die in their sleep. Peaceful, yes, but spiritually absent. Their body remains, but the soul is elsewhere.
Science calls these cases SUNDS — Sudden Unexplained Nocturnal Death Syndrome. Particularly prevalent among Southeast Asian and Pacific communities, it draws clinical speculation about heart issues, genetic factors, and stress. But often, even the best medical minds admit they simply don’t know.
Perhaps because the answer is not physiological. Perhaps it lies just past that dream-thin veil. Perhaps what we call “hallucination” is the mind’s last-ditch effort to explain contact with another plane.
What if the “demon” in sleep paralysis is not a fiction, but a sentinel? A gatekeeper? Or even a warning?
What if the realm we drift into when we sleep is not entirely our own?
The fact that so many remember these encounters — decades later — with clarity and fear, suggests something more than dream. Something real. Something ancient.
To reflect on sleep paralysis is to admit we know less about the mind — and the spirit — than we pretend. It is to stand at the mouth of a cave that opens not downward, but inward, where time and matter blur, and memory clings to sensation like mist to skin.
There may be a world behind our dreams. And sleep paralysis might just be the moment we accidentally wake up inside it.
