Brain freeze

How it works

Cold food touches the palate, the roof of the mouth. The blood vessels there cool very fast. A cluster of nerve cells just behind the nose, the sphenopalatine ganglion, responds to the sudden change¹². Its signal travels along the trigeminal nerve, the main sensory nerve of the face³. That nerve also carries pain from the forehead. The brain cannot tell which branch fired, so it places the pain in the forehead. This is referred pain¹.

One theory adds a second step. The artery at the front of the brain widens quickly to bring warm blood to the area. The sudden change in pressure inside the skull is felt as pain¹. When the artery narrows again, the pain stops.

The pain starts a few seconds after the cold hits and usually ends within a minute¹. Between 30% and 40% of people get it¹. It is more common in people who get migraines¹.

Try it

1. Take a large spoon of ice cream or a big gulp of a cold slush drink.
2. Hold it against the roof of your mouth for a few seconds instead of swallowing.
3. Wait. The headache arrives within about 10 seconds, sits in the forehead, and fades fast.
4. To end it sooner, press your tongue flat against the roof of your mouth, or sip something warm.

If you get migraines, skip this test.

History and culture

The formal name, sphenopalatine ganglioneuralgia, just means “pain from the sphenopalatine nerve cluster”. Doctors list brain freeze in the international headache classification as “headache attributed to cold stimulus”¹.