This article by Theresa Fisher originally appeared on Van Winkles, the publication devoted to sleep.

Annalia first heard the creature slip into her bedroom when she was six years old. It — whatever it was — jumped onto her sleeping body, stifling her movement and speech with its weight. She awoke frightened, seeking an explanation. Everyone in Abruzzo, a small city in southeastern Italy, told her the same thing: Annalia had endured her first visit from Pandafeche, a supernatural being that’s been described as an evil witch, ghost-like spirit and humanoid cat.

The witches, she learned, met on Tuesdays and Fridays beneath a walnut tree, where a chief sorcerer dispatched them to attack sleepers. Even Annalia’s doctor attributed her experience to the evil demon, and advised her to keep salt under her pillow and cups of chamomile at her bedside. These preventive measures didn’t work, however, and the spirit became a recurring presence in the 82-year-old’s life, as was the case for more than a third of the region’s residents.

The term Pandafeche won’t resonate with anyone outside Italy, and even Italians from other regions may shrug in response. But the experience itself is by no means specific to Abruzzo. Somewhere between 20 and 40 percent of people have encountered similar demonic presences climbing onto their chests, leaving them immobilized in the darkness.

The mainstream scientific term for what Annalia experienced is sleep paralysis, but the “right” name for the disorder varies by geographic location, native tongue and worshipping habits. Culturally specific supernatural interpretations are well-known in nations developed and barely developing, secular and extremist alike. Today, some who experience sleep paralysis see Pandafeche. Others encounter oil-slick humanoid figures or jealous old hags with knife-sharp teeth lumbering towards them. Regardless of who gets the blame, one thing is universal among sufferers: a distinctly humanoid figure hovering over the bed.

Regardless of who gets the blame, one thing is universal among sufferers: a distinctly humanoid figure hovering over the bed

And this raises a question that has baffled scientists for decades: Where do these figures come from?

Baland Jalal thinks he knows. Jalal, a neuroscientist at the Behavioral and Clinical Neuroscience Institute at Cambridge University, began dissecting the anatomy of the nocturnal attacks in 2010. For years, researchers had dismissed the phenomenon as an object not worthy of scientific scrutiny, or grant money. When Jalal set out to fill in knowledge gaps, he found a goldmine, ripe for digging.

So Jalal dug. But he didn’t start with the neural nuts and bolts of the disorder like a neuroscientist might. Rather, in order to understand how different cultures interpreted sleep paralysis and how those interpretations affected the attacks themselves, he acted like an anthropologist, reviewing tales of paralysis from victims scattered across the globe.

Papers outlining theories of desynchronized brain activity followed. And Jalal’s grand unifying theory of sorts — the Panic-Hallucination Model of Sleep Paralysis — explains the condition for what it is: a psychobiological phenomenon. But, to break down what was happening inside the brains of sleep paralysis sufferers, Jalal did something that would make most neurologists squirm: He took the mystical sightings — often brushed off as folklore or thrown into the slush pile with alien encounters — seriously. And by doing so, he not only figured out why the supernatural beings appear, but also how to prevent them from shuffling into the sleeping mind.

Understanding the Frozen State

Experts on glitchy brains and strange sleep know that sleep paralysis affects at least 20 percent of the population, including most narcoleptics. The attacks are marked by a loss of muscle control (called atonia) and encounters with violent, shadowy apparitions.

These estimates, however, have only surfaced in the past 15 years. Before then, neurologists thought the condition was rare. But knowledge is often a function of interest, and western doctors and researchers just weren’t interested enough in sleep paralysis to figure out how common it was.

He not only figured out why the supernatural beings appear, but also how to prevent them from shuffling into the sleeping mind

“Perhaps because the phenomenon was so bizarre, scientists and doctors felt inclined to brush it under the carpet, so to speak,” said Jalal. “Perhaps it was easier than trying to understand the underlying brain mechanisms.”

Jalal surmises that misdiagnosis of schizophrenia or psychosis, as well as patients’ failure to report attacks, kept estimates low. “Imagine seeing a ghost with bloody fangs in your bedroom late at night and going to your doctor and telling him about it?” It’s not exactly complaining about a rash or achy knee.

Jalal knows the struggle because he experienced sleep paralysis himself. In 2005, he woke up to the sight of a ghost staring him down. The hallucination, while terrifying, left him intrigued.

Imagine seeing a ghost with bloody fangs in your bedroom late at night and going to your doctor and telling him about it?

Roughly five years later, Jalal began studying the phenomenon. By then, neuroscientists, sleep doctors and psychiatrists had started to fill in a few of the unknowns. Still, Jalal didn’t have much competition. Not from researchers, at least: Filmmakers, DIY consciousness hackers and UFO fanatics had gotten giddy over sleep paralysis for decades. Like them, Jalal saw the biological oddity as something to treasure.

“I realized this was perhaps the most fascinating phenomenon in the entirety of medicine, if not science,” said Jalal. “Here is a single — yet common — phenomenon that can make us see and become ghosts, have encounters with space aliens from distant galaxies, and plunge us into far and exotic lands of lucid dreaming where we are the sculptors of our own realities all while laying silently in our beds.”

His first, move, however, wasn’t to break out the brain scanners. Instead, he and colleagues — including his mentor Vilayanur S. Ramachandran, director of the Center for Brain and Cognition at UCSD, who’s made waves cracking neuroscience mysteries with little reliance on fMRI — set out to dissect sleep paralysis as a cultural phenomenon.

Anatomy of an Attack

The essential features of sleep paralysis persist across time zones and enemy lines. A sleeper partially slips out of REM, either upon falling asleep (a state called hypnogogia) or upon waking up (hypnopompia). They can’t move or speak, but are conscious of their surroundings. In 30 to 40 percent of cases, they perceive something supernatural, the infamous intruder. They might hear it tip-toe into the room and see it loom overhead. In some cases, the ghost physically attacks their body — suffocating or even raping the immobilized sleeper. They may also hallucinate or have an out-of-body experience, in which they become the ghost and hover over their own body.

Still, sleep paralysis isn’t a wholly fixed experience.

In non-Western cultures, research suggests, sleep paralysis is primarily understood in a spiritual framework. In Abruzzo, Annalia blamed Pandafeche for periodically ransacking her night’s rest. In Newfoundland, people talk about the Old Hag. The Japanese blame demons called Kanashibari. In China, the experience is known as “ghost oppression.” Americans may refer to the shadow man or believe they’re victims of alien invasions. Other sufferers steer clear of folklore and blame attacks on screwball neurology.

Jalal suspected interpretive differences of sleep paralysis shaped the experience itself, but he needed to figure out how and to what extent.

Western doctors and researchers just weren’t interested enough in sleep paralysis to figure out how common it was.

So, he and colleagues spoke to lifelong residents of Abruzzo.

“Italy was interesting in its own right because of the fact that it was a “modern” European country, yet stepped in religious tradition as the seat of Catholicism. Surprisingly, we found that 38 percent of Italians believe that sleep paralysis is possibly caused by Pandafeche.”

And compared Egyptians to Danes.

“These countries are so different: Egypt is one of the most religious countries in the world with strong cultural traditions,” said Jalal. “Denmark is one of the least religious countries, where people score very low on measures of religiosity and people usually don’t believe in the supernatural, or at least they don’t admit to doing so.”

Nearly half of participants in Cairo, they found, believed in Jinn, a “spirit-like creature with roots in Islamic tradition.” In Denmark, however, people tended to dismiss sleep paralysis as a brain hiccup. Such divergent views corresponded to different manifestations of the same basic experience.

Sleep paralysis scared Egyptians far more than it did Danes, so much so that University Students in Cairo feared death-by-Jinn. What’s more, a higher proportion of Egyptians endured longer, more frequent attacks — Jinn haunted sleepers in Cairo three times as often as Danish brains went haywire.

Over time, Jalal has spoken to sufferers all over the world, some through his own research, some through theirs. Across different continents, the same trend has emerged: Attacks are longer, harder and more frequent when sleepers hold some supernatural force accountable.

At this point, it might be tempting to give non-believers a gold star and bid them a good (ghost-less) night’s sleep.

Jalal, however, wasn’t — and still isn’t — looking to squash cultural traditions.

Across different continents, the same trend emerged: Attacks are longer, harder and more frequent when sleepers hold some supernatural force accountable.

“There seems to be some tension between supernatural interpretations and so-called scientific ones, and whether they can be in harmony,” he said. “We know for sure that sleep paralysis is caused by certain neurotransmitters activating and deactivating, but at the same time, we don’t want to move towards a society where beliefs that are out of the ordinary should be seen and looked down upon as nonsense.”

To explain how the same basic experience manifested differently for garlic-clutchers and Hitchens acolytes, Jalal came up with the “Panic Hallucination Model of Sleep Paralysis.”

Floating in the Neutral Zone

People are most vulnerable to sleep paralysis when they’re sleep-deprived, jet-lagged or otherwise poorly protected from falling out of REM. It doesn’t take much — just a “few neurochemicals,” according to Jalal — to push the brain into mental no-man’s land.

During an attack, the paralyzed sleeper’s body remains in REM mode. That means shallow, rapid breathing, a hasty heart rate and atonia, the brain’s clever way of preventing people from acting out dreams.

Mentally, however, the sleeper is wading in muck. The dreaming brain activity that enables surreal, crackpot narratives persists. A region called the temporoparietal junction, for example, which regulates the ability to distinguish the self from others, remains inactive. (Think about it: During dreams, it’s perfectly normal for someone to, say, attend a family member’s funeral and see their own slack body in the casket. Perspective is fluid.)

Because sleep paralysis happens in a neutral zone between REM and wakefulness, Jalal explained, brain activity lines aren’t so clear-cut.

Brain activity necessary for awareness of one’s surroundings, which lies dormant during REM, tends to reactivate somewhat. The dorsolateral prefrontal cortex, vital to rational thought, revs back up during an attack. This means that the sleeper can think rationally about vivid, bizarre experiences that challenge laws of time, space, metaphysics, gravity and general good taste.

Still, nothing is set. Because sleep paralysis happens in a neutral zone between REM and wakefulness, Jalal explained, brain activity lines aren’t so clear-cut. The great irony of sleep is that it’s not a state of rest.

Panic and Hallucinations

Jalal’s “Panic-Hallucination Model” explains how belief in a supernatural or mystical being predisposes people to have more and worse attacks — it’s called cultural priming.

Here’s how it works. Say someone with sleep paralysis believes in Pandafeche. At bedtime, they grow anxious about the possibility of waking up to the ominous pitter-patter of the apparition. Their anxiety ignites fear-centers in the brain, which, in turn, increases the likelihood of having an attack.

Later, Pandafeche appears. As she ambles in, the sleeper tries to fight the shallow breathing, but can’t. Nor can they move. These physical symptoms, coupled with awareness of paralysis, incites escalating fear and anxiety, which in turn exacerbates the hallucinations. Fear is an adaptive response, to tip off the brain’s threat detection system against impending doom. Futile attempts to regain motor control actually amplify hallucinatory events: Pandafeche looks more evil; suffocation feels heavier.

That’s the big theory. But Jalal sought to make sense of the gears turning inside the machine, particularly the terrifying spirits. What he did next will reshape the sleep paralysis storyline.

Hunting Apparitions

Explanations for the physical sensations associated with ghost attacks existed before Jalal delved into sleep paralysis. For instance, feeling suffocated under the weight of the intruder could be chalked up to shallow respiration during REM, compounded by panicked attempts to breathe deeper.

To Jalal’s knowledge, however, no one had proposed, or at least published, an explanation for the supernatural intruders. Sure, the figures take on attributes of various mythical figures, but millions of people, from Cambridge to Phnom Penh, hallucinate some variation of the same vaguely human-shaped ghost — this couldn’t be a coincidence.

So, what’s happening? Essentially, the ghost is really the sleeper. Well, it’s a shadow cast by the mind as a result of a functional disturbance in a particular region of the brain.

But, let’s get back to that.

First, let’s talk about Vilayanur Ramachandran. Dr. Ramachandran, or Rama, is a mentor, friend and self-described second father to Jalal. In the neuroscience world, he’s also a living legend, dubbed the “Marco Polo of Neuroscience” by Richard Dawkins. Among other achievements, Ramachandran broke ground in phantom limb pain research.

“I would often raise the topic of sleep paralysis to him during private occasions, say when dining together,” said Jalal of Ramachandran, “or when he invited me to lecture to his students at UCSD.”

Eventually, Rama wanted to help Jalal find an explanation for the ghosts. In fact, he already had. Ramachandran’s work on phantom limb pain became the linchpin in the neurological origin story of the shadowy intruder.

Somewhere between 60 percent and 80 percent of amputees feel the presence of missing body parts — phantom limbs — and that feeling tends to be pain, which can be explained by the brain’s body map. Humans have a hardwired, unchanging template of their physical bodies (called the homunculus) constructed in the right superior parietal lobule, the region nestled just behind the crest of the head that’s responsible for spatial and body awareness. When people feel phantom limb pain, they’re really feeling the presence of the “arm” in their body map.

The ghost appears when the sleeper hallucinates a projection of their own body

Taking this a step further, Jalal believes that this hardwired map also gives rise to the shadowy intruder.

Here’s why: The body map is connected to visual and emotional processing centers in the brain via the same circuits responsible for aesthetic and sexual attraction. This wiring configuration, Jalal says, likely explains why the majority of people are attracted to members of the same species, whose physicality roughly matches their own body maps.

temporoparietal junction_DemonVanquisher

A subregion of the brain, the previously mentioned temporoparietal junction, lies between the temporal and parietal lobes. It’s responsible for integrating self-awareness and the body map (called multisensory processing). In other words, the region lets people distinguish themselves from others. The temporoparietal junction shuts off during REM and the barrier between the self and others dissolves, letting people slide back and forth between perspectives.

During sleep paralysis, this perspective-sliding, coupled with awareness, means that sleepers are prone to creating surreal scenarios that they can consciously rationalize. The ghost appears when the sleeper hallucinates a projection of their own body map, thanks to the silenced temporoparietal junction.

And then the brain puts the story together, because, provided awareness turns on (which it most likely does), the brain is wired to make sense of everything going on. It surveys the chest pressure, paralyzed muscles, ghostly vision and, with help from vivid REM activity, creates sophisticated but fantastical tales of a violent, shadowy interloper with a penchant for smothering.

Connecting the Invisible Dots

If the hardwired body map theory seems farfetched, Jalal has an idea of how to test it. He’d run a clinical trial for people who have both sleep paralysis and some type of dysmorphia, meaning a disorder marked by distorted body image. The trial could, for example, focus on anorexia nervosa or apotemnophilia, in which people with broken, arm-less body maps both want to become amputees and find themselves attracted to amputees. He’d ask participants to describe the creatures they see during sleep paralysis. If he’s right, their ghosts would match the descriptions of their distorted body maps.

In addition to seeing supernatural spirits, paralyzed sleepers also occasionally see phantom limbs and have out-of-body experiences, in which they become their own ghosts. It’s jarring, but not mysterious. Researchers can actually reproduce the phenomenon inside a lab using electrical currents to disturb parietal lobe activity.

Art courtesy of Da Wolf/Creative Commons

Out-of-body experiences happen during sleep paralysis as a result of brain-body desynchrony. When a sleeper realizes they’re paralyzed and tries to wriggle free, the motor cortex in their brain sends messages to their limb muscles to let them move about. The cortex, however, isn’t “aware” that the person is still stuck in REM sleep. Jalal thinks that the parietal lobes monitor communication between the motor cortex and muscles, so that when the cortex fires off a “move” command, it sends extra signals — which Jalal cleverly likens to “CC-ing” — to the parietal lobes.

If the person weren’t stuck between states of consciousness, the muscles would get the message, move as instructed and send feedback to the parietal lobes. But, during sleep paralysis, the parietal lobes don’t get that feedback. Therefore, the sleeper can’t move but may feel as though they do. As a result, the signals bouncing between the brain and body, normally vital to controlling a unified sense of self, are out-of-whack, leading to trippy visions, such as the feeling of hovering over one’s own body.

For most — though not all — sleep paralysis is a scary, if not traumatizing experience.

Though doctors might recommend brain-chemistry-altering drugs to address underlying issues, such as poor sleep or anxiety, no one knows how to treat sleep paralysis itself. So, once Jalal felt he understood the anatomy of the attack, he started working on trouncing it. In a paper published this month in Frontiers in Psychology, Jalal proposes the first-ever sleep paralysis treatment.

Destroying the Dark Creatures

Upon getting learners permits, new drivers are warned not to turn into a skid. The advice bears repeating because the instinctive response to slipping on ice is to steer the car away from the hazard, which only makes an accident more likely. Paralyzed sleepers are a bit like new drivers who don’t get that accident-avoiding tip. As the Panic-Hallucination model suggests, the instinctive response to a sleep paralysis attack — fear and resistance — only exacerbates the severity of the physical paralysis and hallucinatory hell. Knowing that, Jalal created a four-step treatment method to help panicky, frozen sleepers steer into the REM-sleep skid.

The instinctive response to a sleep paralysis attack — fear and resistance — only exacerbates the severity of the physical paralysis and hallucinatory hell.

The simple treatment method, called Meditation-Relaxation (or MR) therapy, comes across as a nod to the mind-body connection — the sort of kumbaya “think good thoughts” exercise that might appeal to yogis more than post-docs. But, the simplicity of the treatment belies the immersive case reports and theories about parietal lobe disturbance that give it heft (and probably lab cred). Unlike treatment for nightmares, MR therapy can be performed during an attack to temper or potentially end it altogether.

Here’s how to defeat the dark figures:

Reappraise the meaning of the attack: Right away, sleepers remind themselves that SP attacks are common, benign and temporary, and that (despite cultural lore), the hallucinations are a product of REM brain activity. They remind themselves to keep their eyes closed, stay calm and avoid movement.

Emotional and Psychological Distancing: Sleepers remind themselves that, because the attack is common, benign and temporary, they shouldn’t be scared or worried. Fear and worry only make the attack scarier and possibly longer.

Meditating: Sleepers focus attention inward, on a strong and emotionally positive “internal object” (i.e. a thought), such as a memory of a loved one or a happy moment, or comforting prayer. They concentrate fully on and actively engage with the thought, and ignore any external stimuli, i.e., hallucinations.

Muscle relaxation: While practicing inward-focused meditation, sleepers relax (rather than flex) their muscles, avoid controlling their breathing and — most importantly — make no efforts to move. They should adopt a “non-judgmental attitude of acceptance toward physical symptoms.”

The treatment is designed both to minimize current attacks and decrease frequency, severity and duration of future ones. For example, the first two steps help reduce the initial panic a sleeper would otherwise feel after an attack begins.

What’s more, Jalal sees potential therapeutic value in teaching people how to induce and manipulate hallucinations. Unlocking the capability could persuade people to see the shadowy figure as a brain-based phenomenon that they can will into existence, rendering it harmless.

It’s hard to deny the culture-science tension inherent in the treatment. To some extent, paralyzed sleepers who attribute the phenomenon to witchcraft, devil’s play or divine intervention need to acknowledge its neurological basis for treatment to work.

In five years, Jalal’s made a considerable dent in sleep paralysis, as a research field. But, it’s only a dent. For starters, his theories need empirical support. That means clinical trials, and perhaps brain activity analysis. He’s studied sleep paralysis in Turkey and has an upcoming hypothesis paper connecting hormones and hallucinations, but says he can’t provide any details yet. Still, his work has already opened a doorway for sufferers, who are finding his research and reaching out for help.

One Scandinavian teenager named Jonah was suffering demonic hallucinations three to five times a week. After learning the tactics and using them for two weeks, Jonah became comfortable using the treatment and, to his relief, shed his fear. When all was said and done, Jonah said he felt soothed and protected.

He also didn’t follow the template verbatim. In step one, rather than remind himself that hallucinations are neurological glitches, he went with “at this very moment, there are millions of people who likewise experience sleep paralysis.”

It worked. The hallucinations grew weaker and less intense. And the occasional nocturnal demon? Not so demonic anymore. Vanquished.

This article by Theresa Fisher originally appeared on Van Winkles, the publication devoted to sleep.