system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why do we get brain freeze?

While eating a big bowl of ice cream I got a brain freeze, and I was wondering why we get them? Mine also appear in my right eye and never "in my brain" for some weird reason.
gpt
When you eat a cold food, the nerves in the roof of your mouth constrict because of the cold. When they expand back to normal size, the blood flow starts coming back, and that's what's known as "brain freeze". All it is is the roof of your mouth returning to normal temperature.  

Pro-tip. Push your tongue to the roof of your mouth, and it will recover quicker, meaning shorter brain freeze.