What Causes Brain Freeze?

Reader Susann writes in to ask, "What exactly is the cause of a brain freeze?"

You may know brain freeze by one of its other names: an ice cream headache, a cold-stimulus headache or sphenopalatine ganglioneuralgia ("nerve pain of the sphenopalatine ganglion"), but no matter what you call it, it hurts like hell.

Brain freeze is brought on by the speedy consumption of cold beverages or food. According to Dr. Joseph Hulihan, a former assistant professor in the Department of Neurology at the Temple University Health Sciences Center, ice cream is a very common cause of head pain, with about one third of a randomly selected population succumbing to ice cream headaches.

So what causes that pain?

As far back as the late 1960s, researchers pinned the blame on the same vascular mechanisms—rapid constriction and dilation of blood vessels—that were responsible for the aura and pulsatile pain phases of migraine headaches.

When something cold like ice cream touches the roof of your mouth, there is a rapid cooling of the blood vessels there, causing them to constrict. When the blood vessels warm up again, they experience rebound dilation. The dilation is sensed by pain receptors and pain signals are sent to the brain via the trigeminal nerve. This nerve (also called the fifth cranial nerve, the fifth nerve, or just V) is responsible for sensation in the face, so when the pain signals are received, the brain often interprets them as coming from the forehead and we perceive a headache.

With brain freeze, we're perceiving pain in an area of the body that's at a distance from the site of the actual injury or reception of painful stimulus. This is a quirk of the body called "referred pain," and it's the reason people often feel pain in their neck, shoulders and/or back instead of their chest during a heart attack.

To prevent brain freeze, try the following:

• Slow down. Eating or drinking cold food slowly allows one's mouth to get used to the temperature.

• Hold cold food or drink in the front part of your mouth and allow it to warm up before swallowing.

• Head north. Brain freeze requires a warm ambient temperature to occur, so its almost impossible for it to happen if you're already cold.

Now, back to Susann. Maybe you flossers can help her out. When she eats ice cream, it's not her brain that freezes, but her back. "I get a back freeze," she says. "What's up with that?" My guess would be it's a neurological quirk that has the brain interpreting the cold stimulus and pain signals as coming from her back. But I'm not a doctor, I just play one on the web. Anyone with a little more authority have a better idea?

[Image courtesy of Donuts4Dinner]

Big Questions
Why Is a Pineapple Called a Pineapple?

by James Hunt

Ask an English-speaking person whether they've heard of a pineapple, and you'll probably receive little more than a puzzled look. Surely, every schoolchild has heard of this distinctive tropical fruit—if not in its capacity as produce, then as a dessert ring, or smoothie ingredient, or essential component of a Hawaiian pizza.

But ask an English-speaking person if they've ever heard of the ananas fruit and you'll probably get similarly puzzled looks, but for the opposite reason. The average English speaker has no clue what an ananas is—even though it's the name given to the pineapple in almost every other major global language.

In Arabic, German, French, Dutch, Greek, Hebrew, Hindi, Swedish, Turkish—even in Latin and Esperanto—the pineapple is known as an ananas, give or take local variations in the alphabet and accents. In the languages where it isn't, it's often because the word has been imported from English, such as in the case of the Japanese パイナップル (painappuru) and the Welsh pinafel.

So how is it that English managed to pick the wrong side in this fight so spectacularly? Would not a pineapple, by any other name, taste as weird and tingly?

To figure out where things went wrong for English as a language, we have to go back and look at how Europeans first encountered the fruit in question, which is native to South America. It was first catalogued by Columbus's expedition to Guadeloupe in 1493, and they called it piña de Indes, meaning "pine of the Indians"—not because the plant resembled a pine tree (it doesn't) but because they thought the fruit looked like a pine cone (umm, ... it still doesn't. But you can sort of see it.)

Columbus was on a Spanish mission and, dutifully, the Spanish still use the shortened form piñas to describe the fruit. But almost every other European language (including Portuguese, Columbus's native tongue) decided to stick with the name given to the fruit by the indigenous Tupí people of South America: ananas, which means "excellent fruit."

According to etymological sources, the English word pineapple was first applied to the fruit in 1664, but that didn't end the great pineapple versus ananas debate. Even as late as the 19th century, there are examples of both forms in concurrent use within the English language; for example, in the title of Thomas Baldwin's Short Practical Directions For The Culture Of The Ananas; Or Pine Apple Plant, which was published in 1813.

So given that we knew what both words meant, why didn't English speakers just let go of this illogical and unhelpful linguistic distinction? The ultimate reason may be: We just think our own language is better than everyone else's.

You see, pineapple was already an English word before it was applied to the fruit. First used in 1398, it was originally used to describe what we now call pine cones. Hilariously, the term pine cones wasn't recorded until 1694, suggesting that the application of pineapple to the ananas fruit probably meant that people had to find an alternative to avoid confusion. And while ananas hung around on the periphery of the language for a time, when given a choice between using a local word and a foreign, imported one, the English went with the former so often that the latter essentially died out.

Of course, it's not too late to change our minds. If you want to ask for ananas the next time you order a pizza, give it a try (though we can't say what you'd up with as a result).

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at

Big Questions
Why Do They Build Oil Rigs in the Middle of the Ocean?

Ryan Carlyle:

We put the rigs where the oil is!

There aren’t any rigs in the “middle” of the ocean, but it is fairly common to find major oilfields over 150 km off the coast. This happens because:

  • Shallow seas often had the correct conditions for oil formation millions of years ago. Specifically, something like an algae bloom has to die and sink into oxygen-free conditions on the sea floor, then that organic material gets buried and converted to rock over geologic time.
  • The continental shelf downstream of a major river delta is a great place for deposition of loose, sandy sediments that make good oil reservoir rocks.

These two types of rock—organic-rich source rock and permeable reservoir rock—must be deposited in the correct order in the same place for there to be economically viable oil reservoirs. Sometimes, we find ancient shallow seas (or lakes) on dry land. Sometimes, we find them underneath modern seas. In that latter case, you get underwater oil and offshore oil rigs.

In the “middle” of the ocean, the seafloor is primarily basaltic crust generated by volcanic activity at the mid-ocean ridge. There’s no source of sufficient organic material for oil source rock or high-permeability sandstone for reservoir rock. So there is no oil. Which is fine, because the water is too deep to be very practical to drill on the sea floor anyway. (Possible, but not practical.)

This post originally appeared on Quora. Click here to view.


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