What causes brain freeze, and why does the pain feel like it is in your

Brain freeze, or a cold-stimulus headache, occurs when the temperature of the roof of your mouth and back of the throat drops rapidly^[1][3]. This sudden chill causes blood vessels in the palate to constrict and then quickly dilate as they warm up^[1]. This expansion activates the trigeminal nerve, which carries sensory information from your face and head to the brain^[3].

Because the trigeminal nerve also senses facial pain, your brain misinterprets these signals as coming from your forehead, a phenomenon known as referred pain^[1]. Pushing your tongue against the roof of your mouth helps warm the area, which can ease the discomfort faster^[3].