The migraine

The hallmark of the migraine attack is a wave of excitation across the brain quickly followed by a wave of inactivity.

The neurochemical changes associated with these waves cause the blood vessels to narrow in the head. Since a lack of blood-flow in the head can be deadly, our body reacts with a massive blood vessel dilation in response. The heightened activity in your brain means you will have trouble moving, thinking, remembering things, and photophobia. In effect, migraines shut us down until the neurchemical balance is restored.