The most disturbing thing about exploding head syndrome is when it hits you. Just in the process of drifting off to sleep, people suddenly think they hear a piercing, crashing noise.

“It’s usually very short, very loud — like a gunshot or explosion,” says Dan Denis, a psychologist with the University of York in the U.K. “It can be pretty scary.”

Many people have experienced this once in their life, and a smaller subset reported recurrent episodes, sometimes as much as once per month. Exploding head syndrome happens between unconsciousness and consciousness and is a sensation that’s intertwined with other sensations. Scientists are just learning more about it, but here’s what they know so far.

The Experience of Exploding Head Syndrome

Despite the “very evocative name,” Denis describes the experience as if you’ve just woken up to a loud crash or bang, rather than any kind of decapitation. The thing is, it’s all in your head — there isn’t any kind of external noise.

This syndrome resembles a hypnic jerk — something that a lot of people occasionally experience while falling asleep, Denis says. Hypnic jerks are the sensation that you are falling, causing your body to suddenly jerk awake.

Silas Weir Mitchell first described these symptoms in the late 1800s in a medical journal, though he used the term sensory shock. J.M. Pearce first used the term exploding head syndrome about a century later, when he published a study that examined 50 patients that suffered from these symptoms in the Journal of Neurology, Neurosurgery, and Psychiatry.

To be sure that was what patients were experiencing, as a result, doctors first had to make sure that there wasn’t an actual noise that woke patients up — say a car crash, gunshot or firework that went off as they were trying to sleep.

Is Exploding Head Syndrome Harmful?

Scientists haven’t found any direct negative impacts from exploding head syndrome. But Denis says that there can be indirect effects. Part of the problem is that this condition isn’t well-studied, even among physicians. As a result, patients may not know what is going on.

“People can think they are going crazy,” Denis says.

Improving public information about the syndrome, or telling them it’s benign, can help the mental stress that some people may otherwise suffer, he says. But it can still cause additional stress, even to people who know what it is. The syndrome could keep someone from sleeping, which could then cause daily stress from the lack of sleep.

Read More: How Our Brains Build Models of the World While We Sleep, Daydream and Hallucinate

The Causes of Exploding Head Syndrome

Since research is slim on the topic, scientists don’t know much about what causes exploding head syndrome. It’s difficult to study, because even the people who experience it a lot may only have it once a month, or so. But Denis says that it seems to be related to other problems with sleep, which are often caused by stress.

“Generally, it’s associated with bad quality sleep overall,” he says.

It’s also possible that the stress of hearing loud noises as someone falls asleep can create a positive feedback cycle, which makes things worse. Patients who experience it may be nervous to go to sleep, which causes further fatigue and stress, thereby increasing the prevalence of the syndrome.

Since it happens just as people are falling asleep, Denis speculates that it may have something to do with the way that the brain shuts off some of its conscious systems, such as the auditory cortex that processes sound. As this cortex shuts off, it may experience a last surge of activity — a kind of misfire — that creates the auditory hallucination of a sound.

“You get this random spontaneous surge in neural firing,” Denis says. “The brain is acting like it heard a sound, but it didn’t hear a sound.”

Can Exploding Head Syndrome be Cured?

Since doctors don’t know what causes the syndrome, it’s difficult to find a precise cure. But a survey conducted among people who suffer from it reported that practicing mindfulness or meditation techniques can reduce its occurrence.

These kinds of techniques, aimed at decreasing overthinking and stress at night, can generally improve sleep overall, which may reduce exploding head syndrome. Some 65 percent of survey participants used these mindfulness techniques and found them effective, Denis says.

Read More: What Happens if the Prefrontal Cortex Is Damaged?

Article Sources

Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article: