The earliest known description of exploding-head syndrome, or EHS, dates back to 1876, when Philadelphia physician Silas Weir Mitchell published his paper “On Some of the Disorders of Sleep,” in the Virginia Medical Monthly. Mitchell described the case of a patient he called Mr. V, who experienced a “sense of a pistol shot or a blow on the head.” Mr. V complained of “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.” In 1920, Sir Robert Armstrong-Jones, a Welsh psychiatrist, described several psychiatric patients whose symptoms included terrifying nighttime experiences with “snapping of the brain.”
British neurologist John M.S. Pearce of the Hull Royal Infirmary in the U.K. introduced the name in a 1988 article published in the medical journal Lancet. Since then, there have been dozens of medical articles written on this bizarre and little-known phenomenon.
What exactly do people with EHS experience? Pearce’s 1988 article describes a common set of symptoms among his 10 patients: “a sense of explosion in the head, confined to the hours of sleep, which is harmless but very frightening for the sufferer.” Pearce published a second article the following year reporting the same phenomenon in 44 additional patients. Today, EHS is defined by the same symptoms experienced by the people in Pearce’s case reports: a sudden loud noise or an exploding sensation in the head, either at the wake-sleep transition or upon waking at night, and abrupt arousal or fright after the event. Some people also see flashes of light, feel hot, experience chest pains and palpitations, or feel an electrical sensation rising from the lower torso to the head.