We know that migraine is a neurological vascular headache and, more importantly, it’s a disease of the brain. That’s basically what we understand now from what we understand about migraine, and it is associated in a number of migraine patients with central sensitization. That means that the pain pathways within the brain and the parts of the brain that understand what pain is and tell you that you’re hurting are turned on and don’t turn off. This is one simplistic way of looking at central sensitization. Migraine also creates significant issues with patients’ ability to work. They can’t work in the midst of a migraine and one of the ways you can find out about their headache is how they act. We now know that patients with migraine can also develop allodynia. Allodynia is severe pain from nonpainful stimulation. It may hurt to comb your hair when you have a migraine--that’s the allodynia--and extracephalic allodynia can cause pain in the back or the hands.
Patients with tension-type headache, which can become extremely severe, can still plod through the day. Tension-type headache is very different because it’s not a neurological disorder or a brain disorder. Most of the time it’s secondary to peripheral stimulation first, meaning it is secondary to muscle spasm, what we used to call muscle contraction headache. You can tell this because if you know how to properly examine the patient, you can actually palpate myofascial or muscular trigger points and trigger points refer pain. Trigger points in muscles in the neck, in the shoulders, and even in the head refer pain in methods and in areas that are identical to the descriptions that you read about headaches.