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.
What Causes Bleeding in the Brain? There are several risk factors and causes of brain hemorrhages. The most common include: Head trauma. Injury is the most common cause of bleeding in the brain for those younger than age 50. High blood pressure. This chronic condition can, over a long period of time, weaken blood vessel walls. Untreated high blood pressure is a major preventable cause of brain hemorrhages. Aneurysm. This is a weakening in a blood vessel wall that swells.