The cause is not known but the existing data suggest a functional upheaval of the intercraneal and extracraneal circulation transmitted genetically. One knows that in the migrañosa crisis regional alterations of the cerebral sanguineous flow exist caused by a intracraneal arterial vasodilatación; in addition one thinks that these alterations can have a causal paper.

Apostulado Seh that the mechanism is related to episódicas reductions of the sistémicas concentrations of cerotonina, which as well, will produce the observed vasomotores changes. The prodrómicos symptoms can be due to a intracerebral vasoconstricción; and there is one who attributes the headache to the substances released by an expansion of the arteries of the hairy leather.

The intracraneales malformations vasculares constitute a rare cause of migrañosa migraine. Migraña can take place to any age, but in general it begins between the 10 and 30 years, being more frequent in the women who in the men. After the 50 years often, the migraines send of partial or total way. In more of 50% of the cases, there are positive familiar antecedents.