The Progressive Era. During the period known as the Progressive Era (1890s to about 1920) the U.S. government became increasingly activist in both domestic and foreign policy.
One possible link between brain freeze and other headaches is local changes in brain blood flow. If further research confirms all these types of headaches are caused by blood flow changes, new drugs that block widening of the blood vessels - called vasodilation - could improve treatment for sufferers.
Brain freeze is practically a rite of summer. It happens when you eat ice cream or gulp something ice cold too quickly. The scientific term is sphenopalatine ganglioneuralgia, but that's a mouthful. Brain freeze is your body's way of putting on the brakes, telling you to slow down and take it easy.