Have you ever been drifting off to sleep when suddenly you hear what sounds like a gunshot, a door slamming, or an explosion inside your head? You jolt awake, heart pounding, sit upright in bed, but the room is silent.

Nothing has happened – but it felt very real.

This experience has a dramatic name: exploding head syndrome.

Despite the alarming name, it’s not dangerous, not painful, and not a sign something is wrong with the brain.

Exploding head syndrome is a type of sleep disorder known as a parasomnia.

Parasomnias are unusual experiences that occur while sleeping or during transitions between sleep and wakefulness.

In exploding head syndrome, a person “hears” a sudden noise that seem to originate from deep inside the head. It’s a sensory perception generated by the brain rather than an external sound.

It typically occurs when drifting in or out of sleep, most commonly when a person is drowsy and about to fall asleep.

People commonly describe a sudden bang or loud metallic noise, gunshots, an explosion, crashing waves, buzzing electricity, a door slamming, or fireworks.

Exploding head syndrome can be intensely frightening. The loud noise may be accompanied by other sensations, including a brief stab of pain in the head (though it’s normally painless), flashes........

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