Do you suffer from "Ice Cream Headache"?
A lot of people do. From www.howstuffworks.com/question96.htm, "Most people have experienced the dreaded ice cream headache at some point. You are minding your own business on a hot summer day and you are eating something like an ice cream cone, a milk shake, a slurpee or a sno-cone. Then suddenly, out of the blue you are hit with the most excrutiating headache in the world! Fortunately they only last about 30 seconds.
"So where do these horrible headaches come from??? I have not seen a better answer to the question than this excellent article by Joseph Hulihan, Temple University. Here's a summary: When something cold touches the roof of your mouth on a hot day, it triggers a cold headache. The cause is a dilation of blood vessels in the head. The dilation may be caused by a nerve center located above the roof of your mouth - when this nerve center gets cold, it seems to over-react and tries to heat your brain. Therefore, the easy way to avoid brain freeze would be to keep cold things away from the roof of your mouth!"
Further to the research on ice cream headache comes the work of a young school student from Canada.