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Some people may also experience heat, strange feelings in their torso, or  a feeling of electrical tinglings that ascends to the head before the auditory hallucinations occur. With the heightened arousal, people experience distress, confusion, myoclonic jerks, tachycardia, sweating, and the sensation that feels as if they have stopped breathing and have to make a deliberate effort to breathe again.The pattern of the auditory hallucinations is variable. Some people report having a total of two or four attacks followed by a prolonged or total remission, having attacks over the course of a few weeks or months before the attacks spontaneously disappear, or the attacks may even recur irregularly every few days, weeks, or months for much of a lifetime. Causes
The cause of EHS is unknown. A number of hypotheses have been put forth with the most common being dysfunction of the reticular formation in the brainstem responsible for transition between waking and sleeping.Other theories into causes of EHS include:

Minor seizures affecting the temporal lobe
Ear dysfunctions, including sudden shifts in middle ear components or the Eustachian tube, or a rupture of the membranous labyrinth or labyrinthine fistula
Stress and anxiety
Variable and broken sleep, associated with a decline in delta sleep
Antidepressant discontinuation syndrome
Temporary calcium channel dysfunction
PTSDExploding head syndrome was first described in the 19th century, and may have first been mentioned in the 17th century. Despite evidence of EHS through centuries, some individuals hold the belief that EHS episodes are not natural events, but are the effects of directed energy weapons which create an auditory effect.