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1_______. It can affect a small portion of the head, such as the eyes or temples, or it can affect the entire head. 2_______. Tension headaches tend to feel like a tightening around the head. Migraine headaches are usually intense and throbbing, often involving one side of the head, although they can affect the entire head. 3_______. There is some thought that an imbalance in the nervous system, especially in the trigeminal nerve, may trigger dilation and inflammation of blood vessels in the head. 4_______.