Question

What IS brain-freeze?​

Answer 1

Answer:

Brain freeze, also called an "ice-cream headache," is known in medical terms as a "cold-stimulus headache," Goldberg said. It's a common phenomenon that affects people of all ages, but doctors aren't quite sure why it happens. [Ouch: 10 Odd Causes of Headaches]

For this type of headache, the main trigger is any kind of exposure to a significantly cold temperature, Goldberg said. It's not only caused by an internal trigger, like eating frozen treats too quickly; it can also be caused by an external trigger, such as going outside without a hat on a frigid day or diving into a very cold lake.