It is hoped the discovery can be used to develop new treatments for migraine.
In experiments carried by researchers at Harvard Medical School and NUI Galway, a team of 13 healthy volunteers deliberately induced the brain freeze so the headache effects associated with it could be studied. It was found that the headache pain was brought on by a rapid increase in blood flow through a major blood vessel in the brain, the anterior cerebral artery. The ache subsided again once blood flow was restricted.
The experimental work, led by Professor Jorge Serrador and carried out at the Cardiovascular Electronics Laboratory in the School of Engineering & Informatics at NUI Galway, enabled brain blood flow to be measured during the controlled onset and offset of a headache. The controlled ‘production’ of a headache was achieved by the volunteers drinking iced water. Using this technique, the researchers were able to study a headache from beginning to end, without the need for drugs that would mask the causes and symptoms of the pain.
The volunteers drank iced water through a straw that was pressed against their palate and then followed by drinking water at room temperature. Blood flow in the brain was monitored using a hand held device. It was found that the anterior cerebral artery dilated rapidly and flooded the brain with blood when the volunteers felt the painful headache, soon after this dilation occurred, the same vessel constricted reducing blood flow, corresponding to the volunteers’ pain receding.
The findings were presented at the meeting Experimental Biology 2012 in San Diego yesterday (Sunday, 22 April, 2012). Presenting the findings, lead-author Professor Jorge Serrador, Adjunct Professor of Cardiovascular Electronics at NUI Galway, and also of the Harvard Medical School and the War Related Illness and Injury Study Centre of the Veterans Affairs New Jersey Health Care System, said: “The brain is fairly sensitive to temperature, so vasodilatation might be moving warm blood inside tissue to make sure the brain stays warm.”
Dr Serrador explained that because the skull is a closed structure, the sudden influx of blood could raise pressure and induce pain. By constricting the blood vessel again the body could be acting to reduce the pressure before it reaches dangerous levels. Similar alterations in blood flow could be at work in migraines, post traumatic headaches, and other headache types.
If further research confirms these suspicions, then finding ways to control blood flow could offer new treatments for these conditions. Drugs that block sudden vasodilatation or target channels involved specifically in the vasodilatation of headaches could be one way of changing headaches’ course.
Keywords: Brain Freeze, NUI Galway
Author: Marketing and Communications Office, NUI Galway