Study reveals cause of 'brain freeze'

 

Brain freeze when eating ice cream too fast: we have all had it, we all hate it. But now at least scientists think they understand why it happens, information that could help migraine sufferers.

Chilled drinks and ice cream bring on the pain when they come in prolonged contact with the roof of the mouth. The pain disappears almost as quickly as the palate warms up again.

NUI Galway researchers contributed to a new study which involved using the pain induced by brain freeze as a proxy for other types of headache including migraine. The focus of the team’s attention was local changes in brain blood flow as a trigger for pain.

Prof Jorge Serrador of Harvard Medical School led the study. He recently completed a Science Foundation Ireland Walton fellowship placement at NUI Galway and this in turn attracted the involvement of Galway’s professor of electrical engineering Prof Gearóid Ó Laighin and PhD student Brian Deegan. Other team members in the US were based at the New Jersey Health Care System.

Brain freeze proved ideal for studying the onset and completion of pain given the shortness of symptoms, Prof Ó Laighin said. Subjects sipped iced water to bring it on and the researchers then used ultrasound to measure the velocity of blood flowing through various blood vessels in the brain as the pain persisted and then dissipated.

The researchers found that one blood vessel, the anterior cerebral artery, dilated immediately as brain freeze arose, flooding the brain with extra blood. The pain then receded as this artery closed back to its normal state.

The researchers speculated that this could be a self defence for the brain, stopping it from cooling too much. The extra blood warms the brain but also causes higher, pain-inducing pressure inside the skull, pain that diminishes when the blood flow reduces.

Similar changes in blood flow patterns could be at work in migraines and other types of headache, Prof Serrador said while presenting his research findings this week in San Diego at the Experimental Biology 2012 meeting.