What is actually happening in my head during a migraine headache?
• The exact biological mechanisms are not known, and may be numerous. One of the most popular theories is that a migraine is caused when a physiological trigger, or triggers, cause vasodilatation (expansion of the blood vessels) in the cranial blood vessels, which activates trigeminal nerve endings in the brain. This results in the release of chemical substances called neurotransmitters, of which the neurotransmitter serotonin is a factor in the development of migraine. During the migraine attack, inflammation of the tissue surrounding the brain also occurs and worsens the pain.
