An ice-cream headache, also known as brain freeze, cold-stimulus headache, trigeminal headache or its given scientific name sphenopalatine ganglioneuralgia (meaning "nerve pain of the sphenopalatine ganglion"), is a form of brief pain or headache commonly associated with consumption (particularly quick consumption) of cold beverages or foods such as ice cream and ice pops. It is caused by having something cold touch the roof of the mouth (palate), and is believed to result from a nerve response causing rapid constriction and swelling of blood vessels or a "referring" of pain from the roof of the mouth to the head. The rate of intake for cold foods has been studied as a contributing factor. Ice-cream headache is distinct from dentin hypersensitivity, a type of pain that can occur under similar circumstances.

Cats and other animals have been observed experiencing a similar reaction when presented with a similar stimulus.

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