What is it?
Exploding head syndrome (EHS) is a neurological condition. While falling asleep or waking up, the person hears an imagined explosive sound like a gunshot or an exploding bomb, or experiences an explosive feeling.
EHS has been relatively little studied. It was originally thought to be quite rare and mainly affect older people, but recently a study discovered that as much as 20% of college students have experienced some symptoms at least once.
EHS is not dangerous, but it is unpleasant. Especially in those who experience symptoms often, the syndrome can have a significant negative effect on their life. While the attacks are not painful in themselves, the noises can be so violently loud and sudden that the sufferer’s brain can sometimes first interpret them as pain.
What causes it?
The cause of EHS is not known, and it is a very little researched topic. It has been found, however, that people going through stress and suffering from physical or mental fatigue are more like to experience it. The stress can get worse when going to sleep because the person knows that new attacks are probably coming, and this anxiety in turn probably makes new attacks more likely. EHS is also associated with episodes of sleep paralysis.
What happens during it?
The mechanism of EHS is not understood, but it has been proposed that the attacks occur when the sufferer’s brain fails to shut some areas down properly when drifting off to sleep. Usually while falling asleep, the neurons associated with senses like hearing and seeing, are gradually shut down. Instead of doing this, it might be that for some reason in EHS all the hearing-related neurons fire at once, causing the loud noise.
How can it be treated?
The treatment of EHS is tricky – partly because the sufferers won’t tell their doctors about it because they are ashamed or don’t think they will be believed. There are no currently approved, safe and effective treatment options, although some medication studies conducted with a very small number of people have been published. Small gestures like explaining to the patient that while what they experience is not nice it is not dangerous has been proven to reduce the number of attacks.
Sources: https://en.wikipedia.org/wiki/Exploding_head_syndrome, http://www.livescience.com/45532-exploding-head-syndrome-sleep-disorder.html, http://syndromespedia.com/exploding-head-syndrome.html#.V-63XTSsvIU