In 1876, two unrelated men described the experience of hearing “loud bells” or a “gunshot,” which would jolt them out of sleep in the morning. Their physician, the father of medical neurology and accomplished novelist Silas Weir Mitchell, coined the term “sensory discharges” to define their disorder. Despite the provocative description, relatively little study had been done on this intriguing concept since its discovery. Flash-forward to 1989 and the British neurologist John M.S. Pierce names the phenomenon: "Exploding Head Syndrome". Yes, you read that correctly: this sleep disorder is called exploding head syndrome.
What is Exploding Head Syndrome?
Contrary to what it sounds like, exploding head syndrome is not like that classic ooey gooey scene in David Cronenberg's 1981 sci-fi horror classic Scanners—where your head explodes at all and any natural circumstance. While the name may blow it a little bit out of proportion, this unusual auditory hallucination is classified as a benign, uncommon parasomnia, but to those who suffer from it, it can be a very real, terrifying experience. In Mitchell’s study, his patient, Mr. V, described his experience thusly: he experienced a “sense of a pistol shot or a blow on the head… a noise in my head, which is sometimes like the sound of a bell, which has been struck once … or else I hear a loud noise, which is most like that of a guitar string, rudely struck, and which breaks with a twang.”
What does it mean to have exploding head syndrome and is it something you should worry about developing? Is there a cure? To answer these questions, we must understand what exploding head syndrome is—a parasomnia.
What is Parasomnia?
Parasomnias are a category of sleep disorders associated with abnormal movements, behaviors, perceptions, emotions, and dreams that occur during many stages of sleep—whether falling asleep, sleeping, between sleep stages, or during arousal. Parasomnias can take many abstract forms as one’s level of awareness and cultural biases can make for some pretty horrific, lasting experiences. The dissociation from reality that parasomnias cause can be attributed to any combination of genetics, PTSD, side effects of medication, or other disorders such as REM sleep behavior disorder, and it is likely that parasomnias occur more often alongside stress and bad sleep hygiene. It is difficult to pin down exactly how to avoid this diverse set of sleep disorder symptoms, though cognitive behavioral therapy or pharmacological interventions have been shown to improve symptoms. Parasomnias show themselves in a wide variety of fascinating ways, many of which have been the formula for horror and science fiction stories throughout time.
Sleep Paralysis - This is one of the most common parasomnias, an unusual sensation characterized by temporary paralysis upon waking, often accompanied with hallucinations of a demonic or physically-imposing nature.
Supernatural Demons - From the Brazilian Pisadeira (a gaunt, unkempt old man or woman who sits upon your chest while you sleep) to the Cambodian khmaoch sângkât (the ghost or sleep paralysis demon that pushes you down), individuals’ experiences believing to have been visited by sleep paralysis demons have become the stuff of folklore.
Alien Abductions - The prevailing theory is that alien abductions may be a result of undiagnosed sleep paralysis hallucinations manifesting as a collective visualization of unknowable creatures.
Nightmare Disorder - More than your ordinary nightmare, sufferers of nightmare disorder have recurrent fear-inducing dreams with awakening dysphoria that impairs sleep or daytime functioning. Have you ever experienced a dream that felt so real it affected your mood?
What Causes Exploding Head Syndrome?
People who experience exploding head syndrome are not simply inconvenienced upon waking up in the morning, there are cases of the disorder not only preventing sleep by jarring a person awake as they’re falling asleep, but also cases of prolonged fears associated with the condition. Some awaken in a pool of sweat or with heart palpitations from the experience.
Exploding head syndrome is considered an NREM-related parasomnia, and researchers believe that it has to do with brainstem reticular formation, the area of your brain that regulates eye movement, motor control, reflexes, and the transitions in and out of sleep and wakefulness. As we approach sleep, this part of the brain turns off these functions so that we can go into our semi-paralytic sleep state for the night. Those with EHS are likely experiencing a disconnect between the NREM stage (our initial stage of entering or final stage of exiting) of sleep and waking life. Normally, when we fall asleep, our body shuts down our motor functions and perceptive systems so that we stay in bed (sleepwalkers have a disconnect here as well).
No definitive risk factors have been firmly established, though the top causes of sleep disorders—stress, fatigue, emotional distress—are all likely suspects.
When disrupted, the rapid firing of neurons in in your brain seems to activate these perceptive areas and cause auditory hallucinations (*BANG!*) sometimes accompanied by physical manifestations through muscle spasms (unexpected sharp pains or thumps). The feelings we can experience during the transition between NREM sleep and wakefulness can have pretty unbelievable and strange consequences.
Will Exploding Head Syndrome Kill You?
In a 2013 study by Gautam Ganguly et al., the team researched exploding head syndrome, focused around a 57-year old man who had experienced symptoms of the sleep disorder his whole life. After a neurologic examination, they concluded that “EHS is a benign, uncommon, predominantly nocturnal parasomnia that can mimic primary and secondary headache disorders along with seizures. No treatment is generally required as the condition is self-limiting. Reassurance to the patient is often all that is needed.” That last line is really telling. Reassurance. Everything is going to be okay.
Put Your Exploding Head to Rest
That kaboom, clang, bang, bong, smash, or clash you hear when you’re about to fall asleep at night or that jolts you out of bed when you’re in the middle of a dream… it’s likely caused by a disconnect in your REM and waking states, and, like many sleep disorders, one of the many strange ways our bodies cope with excessive stress. But, as Ganguly and team pointed out, even if you suffer from exploding head syndrome, it’s all going to be okay—just try to manage your stress and anxieties and likely it’ll end as suddenly as it began.