Migraine Causes in Plain English
By Jared Paulson

 

“What causes migraines?” As someone who treats a lot of migraineurs, I often hear this question. People are often confused by huge technical words, old theories, and simple bad information. The causes of migraines are very complex, and the process is not completely understood yet. However, much has been learned in the past several years to explain this disease.

 

Sensitive Brains

Migraines are a primary disorder, meaning that they are not caused by other problems in the body; they are the problem. Migraines are characterized by abnormal changes in nerve function and blood flow. The easiest way to describe a migraineur’s brain is that it is much more sensitive to change than other people’s. Changes in the environment, stress levels, and certain foods can set off a cascade of nerve activity resulting in intense pain. This activity starts deep within the brain and spreads to the nerves on the outside of the head thus leading to pain.

 

Blood Flow

It was once thought that migraine pain was caused by increased blood volume in the vessels of the brain leading to increased pressure. It is now known that this is not true. While this increase in blood flow is part of the migraine, it is not the primary cause of pain. The pain is a result of nerve dysfunction. However, blood flow changes are a major symptom of migraines. Many migraineurs have cold hands and feet before or during migraines as a result of these changes in blood flow.

 

Angry Nerves

There are two nerves usually involved with migraine pain. The trigeminal nerve, which goes to the face and eye area, and the occipital nerve, which starts at the back of the head and moves forward along the side of the skull to the forehead. These nerves become inflamed as a result of the migraine process and lead to intense pain. Sometimes people with migraines will also experience abdominal pain. The process is essentially the same but involves different nerves. These are called abdominal migraines. The nerve involved will dictate where your migraine occurs.

 

Pain Sensitivity

A migraineur also has a malfunction in the pain control system of the brain. When you are kicked in the leg, your brain processes the nervous input and registers pain. Normally, once it has done this the brain begins to “turn down the volume” on the nerves causing the pain. People who suffer from migraines have a problem with this pain control mechanism. When the migraine process is triggered, it turns off this pain control system causing previously manageable sensations to become excruciating. Migraineurs are more sensitive to many sensations. For example, they are much more likely to get “ice-cream headaches.”

 

Daily Changes

So what determines when you get a migraine and when you don’t? Your sensitivity changes from day to day. Things like stress and lack of sleep or exercise can tax the body and make you more likely to develop a migraine. That is why you may, for example, usually be able to have a glass or two of wine but occasionally pay for this indulgence. The so-called migraine threshold is a measurement of this sensitivity. Controlling the sensitivity of your nervous system is key to managing your migraines. When your doctor gives you daily medications for your migraines, the goal is to decrease this sensitivity.

There are many pieces to the migraine puzzle. While we do not have all of the pieces yet, we are now starting to understand the big picture of what is happening. More and more is being learned every day thanks to the efforts of many dedicated researchers. This research is constantly leading to improvements in migraine management and hopefully migraine pain will be a thing of the past in the near future.