Brain ChemicalsAnother theory on migraine causes focuses on chemical changes in the brain. When chemicals in the brain that send messages from one cell to another -- including the messages that signal blood vessels to get narrow or expand -- are interrupted, migraines can occur.
More recently, genes have been linked to a possible migraine causes. People who get migraines may inherit abnormal genes that control the functions of certain brain cells. Something that the person's body is, in some way, sensitive to also triggers the actual headaches.