Scientists have discovered a surprising brain trigger for high blood pressure in a small area of the brainstem that normally controls breathing. This area is activated during forceful exhalations such as coughing, laughing or exercise. When activated, it activates nerves that constrict blood vessels and thus increase blood pressure. In experiments, researchers turned off this area and blood pressure dropped back to normal. This suggests that this area plays a direct role in hypertension. The discovery may lead to new ways to treat high blood pressure.