Background Exploding head syndrome (EHS) is characterized by loud noises or a 
sense of explosion in the head during sleep transitions. Though relatively 
common, little is known about its characteristic symptoms or associated 
features. Methods A cross-sectional study of 49 undergraduates with EHS was 
performed. A clinical interview established diagnosis. Results The most common 
accompanying symptoms were tachycardia, fear, and muscle jerks/twitches with the 
most severe associated with respiration difficulties. Visual phenomena were more 
common than expected (27%). EHS episodes were perceived as having a random 
course, but were most likely to occur during wake-sleep transitions and when 
sleeping in a supine position. Only 11% reported EHS to a professional, and 8% 
of those with recurrent EHS attempted to prevent episodes. Conclusions EHS 
episodes are complex (Mean (M) = 4.5 additional symptoms), often multisensorial, 
and usually associated with clinically-significant fear. They are rarely 
reported to professionals and treatment approaches are limited.