To date there is has a base that can say that is the cause of the disease or its origin is believed to occur a sobreexitacion at the neuronal level that generates spasms in the arteries of the brain and its subsequent expansion generates a constriccion on the nerve causing the pain. What is known is that certain factors descencadenantes as, the stress , the bad food , sleep poorly or too much, environmental factors such as the exesivo heat , lack of physical activity , and to some extent to genetic factors..