Migraine headaches are neurogenic/vascular1 headaches caused by abnormal nerve control of blood vessels that supply the brain.  Sympathetic nerves control the diameter of blood vessels; when they lose proper regulation, they fire too much, causing blood vessels to constrict.  Constriction of blood vessels decreases blood and oxygen to brain cells.  The visual area of the brain is a common area to be affected; this is why many migraine sufferers experience an “aura” or visual disturbances before pain starts.  Other migraine sufferers may have different aura sensations, while some have no aura at all; occasionally auras occur with no pain.

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