Migraine is caused mainly by the contraction of the muscles around the neck, shoulder tense, until occur a small cube approximately 0.5-1.0 cm. The blood and oxygen to the brain cannot spot it. As a result, the blood and oxygen cannot be fully passed on to the head. So the blood cannot be sent up to the brain in the head, the two sides are not equal. Thus causing a headache one side. Called migraine.