How Many Beliefs Are Due to Sleep Deprivation?

Fyodor Dostoevsky kept a record of his seizures in a notebook. There were 102. Today some people with epilepsy do the same on Pinboards. Those less candid among the epileptic Pinterest community post empowering quotes: "Don't flatter yourself. I wasn't staring at you. I have petite mal seizures."

The petite mal is a seizure not often diagnosed until it has been happening for quite a while. It involves no convulsions, only a person staring off, as if lost in thought. The spells often last just a few seconds. A child who has petite mal seizures might be dismissed as inattentive. Under that mistaken presumption, he might be given Adderall, when the real problem is a seizure disorder.

Sometimes Dostoevsky did convulse in a more Hollywood seizure fashion, even foaming at the mouth. He also slipped into outwardly subtler "ecstatic" seizures, which rendered him blissful. Actually, that's extreme understatement. "I would feel the most complete harmony in myself and in the whole world," he once said of the episodes, "and this feeling was so strong and sweet that for a few seconds of such bliss I would give 10 or more years of my life, even my whole life perhaps.”

Those auras most likely originated in the temporal lobe of his brain, where biochemical lapses can cause bursts of terror or euphoria that run the gamut from fleeting to life-altering. Oliver Sacks told in this magazine the story of a bus driver who, in the midst of a temporal-lobe seizure, collected fares while telling passengers how pleased he was to be in heaven.

Déjà vu is often caused by misfiring of neurons in the same region. If you take those retrograde premonitions as signs of divine intervention, as signs of being on your intended path, as messages from a higher power, you are in good company. Dostoevsky, like the bus driver, immediately explained the sensation as a concrete encounter of the sort many intellectuals are skeptical: "I have really touched God. He came into me myself; yes, God exists, I cried. ... Mahomet, in his Koran, said he had seen Paradise and had gone into it. All these stupid clever men are quite sure that he was a liar and a charlatan. But no, he did not lie."

Nor are the people who make no claim to divinity, only to Exploding Head Syndrome, liars. You probably do not have Exploding Head Syndrome, according to the best statistical estimates of sleep researchers. If you did, you would know. Especially after the attention that the condition—known to insiders simply as Exploding Head—has gotten this week.

The name lacks a certain subtlety. But "explosions in my head" is exactly how sufferers tend to describe it: the perception of cacophonies while falling asleep or waking up, jerking a person into consciousness. And by innumerable accounts in news media, the condition may, according to new findings published on Tuesday in the Journal of Sleep Research, affect many more young people than experts previously appreciated.

Exploding Head is named for the sensation it elicits, rather than an actual explosion of the head. Learning that was at once heartening and a little disappointing. If you scour the corners of the Internet, as I tend to do, you'll find plenty of people who say they have Exploding Head. And plenty of sufferers don't believe it's a natural biological phenomenon. Instead they attribute it to the government harassing them, often using microwave technology, essentially torturing them with sleep deprivation through electromagnetic radiation. When outlandish things start happening in our bodies, outlandish explanations start to seem less outlandish.

Among academics, there are a handful of theories as to what causes Exploding Head. Those theories include temporal-lobe seizures and dysfunction among the tiny bones in the middle ear. Institutionalized torture is not among them. Brian Sharpless, a clinical psychologist in Pullman, Washington, who has taken a keen interest in the study of Exploding Head in recent years, favors the colloquial explanation that the auditory bursts amount to "a hiccup of the brain." When you're shutting down for sleep, you have to go through a series of steps, shutting off auditory neurons, motor neurons, visual neurons, et cetera. Explosions happen when, instead of shutting down, auditory neurons fire all at once.

"My gut would tell me that things like anxiety and insomnia, and a general preoccupation with bodily symptoms and fear of them, would make people more likely to have Exploding Head," Sharpless told me. The bursts of noise are usually painless, but also usually accompanied by fear and distress. People who are sleep-deprived are more likely to experience explosions, which leads to a question of what is causing what. And, rarely, to a horrible cycle of worsening insomnia and worsening explosions.

Sharpless has to go with his gut because the scientific literature on the topic is scant, if slightly less so after this week. It was he who published the news-making findings on just how common the syndrome is. The message in widespread coverage is summed up in what was the most-popular story at New York magazine on Wednesday: "A Fifth of College Students May Have 'Exploding Head Syndrome.'"

That seems high. It also seems to validate Sharpless's hypothesis, covered in this magazine in January, that Exploding Head Syndrome is more common than long thought. Similar phenomena have been described since at least 1876. Between then and the naming of Exploding Head Syndrome by neurologist John M.S. Pearce in 1988, it has usually been described as an obscure occurrence. Certainly not one that most people have heard of. In his initial Lancet article on the condition, Pearce did note a suspicion that it was "common and underreported," but he, too, had to pull that from his gut.

In 2008, one German study suggested that 10 percent of the population is affected; but that was based on self-reported surveys, which are unreliable. Sharpless's findings, part of his work at Washington State University, are based on diagnostic interviews with clinicians. Though the number of people studied—211—is not large, and all of them were undergraduates, the findings do suggest that Exploding Head is indeed a regular occurrence in young people.

"My lab studies several strange disorders," he explained. "Well, putatively strange. I find them interesting." Among those things is isolated sleep paralysis, where a person is conscious and awake but cannot move. Hallucinations are common during those episodes. People with sleep paralysis are more likely to have Exploding Head. And indeed, the study Sharpless published this week included a disproportionate number of people with sleep paralysis. Accounting for that sampling bias, the prevalence of the condition drops to 13 percent. And it drops still further when you note that that number includes all people who have ever experienced an explosion. If you look at the people who had Exploding Head to the point that it actually caused significant distress and interference in their lives, it was only 2.8 percent.

Which still seems high. How has everyone not heard of this? Sharpless believes that if people did know about Exploding Head, and talked about it, fewer people would chalk their symptoms up to serious illness and supernatural occurrences. So the harm in overestimating, as a point for raising awareness and making headlines, is minimal. In my case, I hope we go with, "Is Your Head About to Explode? Probably." [Ed. note: No]

Everyone has felt anxious or depressed, but most people have not been debilitated by unrelenting anxiety and depression. Somewhere in between, a diagnosis is warranted. Exploding Head Syndrome can be found in the International Classification of Sleep Disorders, but not the Diagnostic and Statistical Manual (the guiding textbook used in American psychiatry). Generally the delineation between a symptom and a behavioral or functional disorder is drawn when that symptom "causes significant distress or impairment."

The relative obscurity of the syndrome is, Sharpless believes, what leads people to abide outlandish reasoning, to make sense of the outlandish thing that's happening inside their heads. The experience, and the beliefs that can accompany it, actually shape people's perspectives and behaviors in other aspects of life. "People need explanations," said Sharpless, "so this becomes a way to use a conspiracy theory to explain away a strange sleep condition. The causality is tough; are people more likely to believe in ghosts because they have these sleep conditions, or vice versa? Probably a little bit of both."

It's the same thing with isolated sleep paralysis; you're essentially dreaming while you're awake and seeing hallucinations. So people tend to believe they're seeing ghosts. If you look to early European vampire literature, Sharpless told me, and you add sleep paralysis and tuberculosis together, you have a pretty good explanation for vampire beliefs. Tuberculosis leads to inflammation in the lungs, so they fill with fluid, and that disrupts sleep. That makes you more likely to have sleep paralysis. You might also have been coughing in your sleep, so you wake up with blood on your pillow. Most vampire tales started with one person in a tiny village, and then it spread through the family, and then the village, following disease transmission patterns.

How much extreme distrust of the government is just a manifestation of a sleep disorder? "I think when you have people who are already mistrustful of the government, for example, you can use those beliefs to try and explain strange things that happen to you," said Sharpless.

By themselves, he explained, the episodes are harmless. Pearce likewise described the explosions as "entirely benign." Rather, the pathology draws from the reaction to the phenomenon. "If you think there's something seriously wrong with you. If you think you're going crazy," said Sharpless, especially if you are not believed, isolation and distrust ensue.

After Dostoevsky died, Sigmund Freud armchair-diagnosed him with "hystero-epilepsy," dismissing the author's detailed accounts as "alleged epilepsy." Rather than an organic brain disorder, the condition had to have been an affectation, some manifestation of Dostoevsky's relationship with his father—because, Freud believed, no one of great intellect could have epilepsy. That dismissal of disease is what people who today curate epilepsy-empowering Pinboards are still working to undo.