Fact: ‘Brain freeze’ has a biological explanation.

It even has an unpronounceable name: sphenopalatine ganglioneuralgia. When something very cold touches the roof of your mouth (called the ‘palate’), it rapidly cools the blood in the small blood vessels around your sinuses. This causes them to constrict, and then to rapidly dilate again when the blood warms up again (which happens when you stop necking ice cream to take a breath).

Pain receptors in your mouth detect this relaxation of the blood vessels, but due to something called ‘referred pain’, it feels like the pain comes from your forehead, even though the signals originated in the roof of your mouth. This is because the same nerve carries signals for facial pain and palate pain, and because you’re just more used to being slapped in the face than in the roof of your mouth you assign this pain to your forehead as a force of habit. Researching brain freeze might seem pointless, but scientists actually use it as a model for other headaches that are not understood as well, such as migraines, so somewhere out there there’s probably a scientist that will pay you to eat ice cream as fast as possible. Time to sack off those consultancy applications. Another one of Mr. Aran Shaunak’s Little Bites of Science @BitesOfScience