Exploding head syndrome is a condition that causes the sufferer occasionally to experience a tremendously loud noise as originating from within his or her own head, usually described as the sound of an explosion, roar, gunshot, loud voices or screams, a ringing noise, or the sound of electrical arcing (buzzing).
This noise usually occurs within an hour or two of falling asleep, but is not necessarily the result of a dream and can happen while awake as well.[1] While the sound is perceived as extremely loud, it is usually not accompanied by pain. Attacks appear to change in number over time, with several attacks occurring in a space of days or weeks followed by months of remission. Sufferers often feel a sense of fear and anxiety after an attack, accompanied by elevated heart rate. Attacks are also often accompanied by perceived flashes of light (when perceived on their own, known as a "visual sleep start") or difficulty in breathing. The condition is also known as "auditory sleep starts". It is not thought to be dangerous,[1] although it is sometimes distressing to experience. Sufferers may experience an inability to vocalize any sound, or mild forms of sleep paralysis during an attack.
Reference to the condition was made in an episode of the ITV drama Doc Martin, which was instrumental in many sufferers becoming aware that the problem was in fact a known medical condition, and not one to be concerned about.