A brain freeze is a short, intense pain behind the forehead and temples that occurs after eating something cold too fast. If you get one, don’t worry – nothing is happening to your brain. The sensation feels like it’s happening inside your skull, but it really has to do with what’s going on in your mouth. Most agree that eating or drinking something cold, too quickly, rapidly lowers the temperature at the back of your throat and the roof of your mouth. Many also agree this causes the tiny blood vessels in these areas to shrink, allowing less blood to pass through them.

Source: The Conversation