A version of this article originally appeared on VICE Indonesia.
In Indonesia, it goes by many names: rep-repan, eureup-eureup, and tindihan. The Hmong people of Vietnam and Laos call it dab tsong. In Cambodia, it's khmaoch sângkât. In every country, there's a common thread that runs through local explanations of what Western doctors call "sleep paralysis": It's the work of some kind of spirit, or, to translate the Khmer phrase, it's literally "a ghost pushing down on you."
It's something I've suffered from my whole life. Many Indonesians sleep away the hunger and thirst that comes from fasting for Ramadan. Not me. To others, sleeping is this restful thing, but for me it can be exhausting.
Nearly every time I fall asleep I end up waking up with a jolt. But "waking up" isn't the right phrase because I'm not exactly conscious. I'm somewhere in-between instead, in that weird and sometimes scary space between sleep and awake. I lie there unable to move but totally aware of my surroundings. Want to hear the most fucked up part? I swear that I can see something black get up off my body and walk through the wall next to my bed. I can feel some weird otherworldly warmth leaving my body.
This has happened nearly every night, sometimes 20 times in a night, since I was six years old.
"I was horrified. I couldn't tell if it was real or a nightmare. I couldn't move. I freaked out."
So what the hell is it? Some Indonesians believe sleep paralysis is the work of jin—spirits or ghosts named in the Quran as one of God's smartest creations. Jin aren't always malevolent, but they are spirits, and that still makes them pretty damn frightening if you ask me.
Four years ago Mirella Pandjaitan, 22, experienced sleep paralysis for the first time in her life. She immediately thought of evil spirits.
"I was horrified," Pandjaitan says. "I couldn't tell if it was real or a nightmare. I couldn't move. I freaked out. Back then I didn't think it was sleep paralysis because I wasn't familiar with the term. I thought a bad spirit had tried to bother me because I too have experienced waking up [to see a ghost]. I couldn't go back to sleep."
"You experience hallucinations, you can see some sort of creature, but the form this creature takes really depends in your cultural background. That's why different people in different parts of the world see different things."
Knowing I wasn't alone was a bit of a relief, but it wasn't much. I needed to get to the bottom of this to figure out if I will ever get the chance to have a good night's sleep this Ramadan. So I got in touch with Andreas Prasadja, Indonesia's only sleep disorder specialist. He says that disorders like sleep paralysis can get worse when you're fasting.
"People who are fasting experience a shift in their biological clock; they're lacking sleep," Prasadja says. "And in extreme cases, sleep deprivation could trigger sleep paralysis."
I meet Prasadja at Mitra Hospital in Kemayoran, Central Jakarta, where he runs a sleep disorder clinic and I go through my experiences with him. Prasadja nods then told me what's behind by nightly ghost visits.
When we're in the REM sleep, or the "rapid eye movement" phase of sleep, we're most at risk of suffering from sleep paralysis. This occurs when there is an overlap between REM sleep and wakeful brainwaves, Prasadja explains.
"There are two characteristics of sleep paralysis," Prasadja says. "The first that is you experience hallucinations—you can see some sort of creature, but the form this creature takes really depends in your cultural background. That's why different people in different parts of the world see different things."
Here in Southeast Asia, we see ghosts. In the US, a lot of sleep paralysis sufferers see spiders. My editor, an American, told me he sees kittens instead.
The second characteristic of sleep paralysis is what gives it its name.
"You're unable to move due to [your body's] neural defense mechanisms," Prasadja says. During normal sleep, it's unsafe for your body to move—just imagine all the trouble you could get into that way. US doctors started to study Southeast Asian experiences with sleep paralysis when refugees from Cambodia, Laos, and Vietnam began to arrive in the country. Cambodian refugees, struggling with the trauma of surviving the Khmer Rouge's death camps, were complaining of khmaoch sângkât. Then suddenly, in the early 80s, more than 100 otherwise healthy Hmong men died in their sleep. No one could understand what was going on. Doctors decided to call it Sudden Unexplained Nocturnal Death Syndrome or SUNDS.
And then, just as sudden as it appeared, the deaths stopped. More than two decades later a professor from the University of California, San Francisco, came to a chilling conclusion: The Hmong people's belief in the dab tsong, or night spirit, is what killed them.
Well, sort of. Technically it was likely a heart defect that caused their deaths. But sleep paralysis, and their own local beliefs on what was causing it, also played a vital role, Adler argues in her book Sleep Paralysis: Night-mares, Nocebos, and the Mind Body Connection. Beliefs, she concludes, have the ability to kill.
Halfway across the country, a cardiologist at the Baylor College of Medicine, in Texas, was looking into alleged connections between SUNDS, REM sleep, and sleep paralysis. The doctor, Matteo Vatta, found that Southeast Asian men were predisposed to a genetic heart arrhythmia that was possibly behind the deaths of the Hmong men back in the 80s.
"The heart can be normal for quite some time, and then it may stop unexpectedly," Vatta told the blog LiveScience. "Usually, the heart stops at night, and in Southeast Asia it once caused more deaths amongst young males than car accidents." Vatta believes the genetic heart arrhythmia and sleep paralysis are connected. He says the deaths occur at night because a person's heart beats more weakly during sleep. When the heart slows down during sleep, the electrical problems that trigger SUNDS become more pronounced, override the body's ability to regulate its own heartbeat, and send the organ itself into a deadly spasm. While there have been some theories that assert the onset of SUNDS is linked to nightmare-induced stress, no scientific studies have confirmed a correlation between SUNDS-caused deaths and dreams.
But don't worry, SUNDS and rep-repan aren't the same thing. Sleep paralysis is just a common problem, and it's best to ignore it when it happens to you, Prasadja says.
"It can't harm us when it's happening, but it does have bad implications," he says. "[Sleep paralysis] is a sign that someone is extremely sleep-deprived. So if you're driving car or motorcycle under that condition, it could be fatal, no?"
The Hmong men were likely terrified when it happened to them. So what's Prasadja's advice? Stay calm and go back to sleep. "Just don't fight it, it's exhausting," he says. "Just go back to sleep. Everything is OK, even though it seems and feels terrifying."
It's not just Southeast Asians who find the whole experience frightening. The word "nightmare" allegedly comes from the Norse term "mare"—a supernatural spirit or power that likes to crush people's chests or choke them when they sleep.
In Indonesia, beliefs tend to be passed down from generation to generation, so it's no surprise that some weird old ideas about evil ghosts are still popular today. Or is it not that weird at all? Science is great and all, but what if that dark figure I see at night really is a ghost?
I contacted Risa Permandeli, an expert in Indonesian ghosts and mysticism, to ask why these beliefs were still so prevalent in Indonesia.
"Our people just accept the information they get, and they never change their views," Permandeli says. "There have not been any efforts to counter the idea or verify it. We're never preoccupied by the notion that we need to verify something."
So in a country where there is a widespread belief in the supernatural, ghost stories and old-fashioned lore persist.
"In Indonesia we believe in the unseen world," Permandeli says. "We never said that the unseen is separate from our lives, so we take it as fact that something that can happen at any moment.
"I think anywhere in the world, even in France where people are known to be rational, there's a concept of the unseen world. In Western, Europe the belief of an unseen world stopped when they discovered rationalism. Here, there's no such thing as knowledge-based rationalism, so our traditions and myths live on."
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