【趣谈英语】大脑本身感受不到痛苦-Your Brain Feels No Pain

You can whine about an earache⁵ or a headache, but you can’t complain about pain in the brain. The human brain has no pain receptors. It can’t tell itself that it hurts. If the brain feels no pain, what is brain freeze? Brain freeze, also called an ice cream headache, occurs when you eat or drink something cold too quickly. When ice cream touches the roof of your mouth, the blood vessels⁶ in your mouth contract. This sends a message to the brain about a change in your body heat. The brain overreacts and tries to conserve heat by contracting the blood vessels in your head. When the threat is over, the blood vessels in the head relax and dilate. This sends a quick rush of blood to the head. You feel this rush of blood as pain in your temples, face, or neck, but not in your brain. Try pressing your tongue against the roof of your mouth to relieve the sensation of brain freeze.