Cold-stimulus headache
A cold-stimulus headache, colloquially known as an ice-cream headache or brain freeze, is a form of brief pain or headache, commonly associated with consumption (particularly quick consumption) of cold beverages or foods such as ice cream, popsicles, slushies, and snow cones. It is caused by a cold substance touching the roof of the mouth, and is believed to result from a nerve response causing rapid constriction and swelling of blood vessels, "referring" pain from the roof of the mouth to the head.