Practical Neuropsychiatry

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Migraine 101

In popular culture, a migraine is a really bad headache. In truth, migraine isn't really a headache syndrome at all. Migraine is actually a sensory processing disorder. Have you ever noticed that the light bothers you, the sound bothers you... and the people bother you? 

Books and books could be written on migraine, but patients shouldn't have to get a medical degree to get relief. More importantly, some of the symptoms of migraine can be terrifying, making patients rush to the emergency room for fear they are having a stroke. While patients should always go to the ER with a new stroke like symptom, understanding the symptoms of migraine can reduce fear when they are sent home by the ER doc who says "everything came back fine."

The headache from migraine was long thought to be caused by spasming blood vessels, but this theory doesn’t hold much water. Migraine begins with a cascade of chemicals, chiefly dopamine, deep in the brainstem. This leads to signals traveling down the nerve for facial sensation called the Trigeminal nerve. This nerve also sends signals to and from the Meninges (the skin between the brain and the skull). In a process called “sensitization” chemicals are released in the brainstem to amplify sensations from the meninges, and inflammatory markers are released in the meninges leading to often severe head pain. While patients will say their “brain hurts”, it is really this meninges tissue that is to blame. Technically the brain doesn’t have pain receptors, which is why they can perform brain surgery while people are awake. So this meninges pain is the migraine headache, but there are a lot of other pains in migraine. 

The second most common pain from migraine is the skin sensitivity of the head and neck called “allodynia”. People feel like their hair hurts, or their skin burns. If the “sensitization” happens at higher levels in the brain, people can feel zapping, tingling, or burning throughout their body. In some people, this sensitization becomes a whole body experience. Most of the patients I meet with the dreaded “fibromyalgia” had migraines when they were younger, even if now their pain syndrome affects their whole body. However, some of the most terrifying symptoms in migraine aren’t pain at all. In fact, people can have migraine associated perceptual disturbances without a headache at all. They used to call this a silent migraine, but losing vision or being unable to feel half of your body doesn’t feel very “silent” to patients. So how do these strange symptoms happen, and what does it have to do with a headache? 

Remember that dopamine cascade we talked about? One pathway leads to pain amplification, but the other can lead to a process called “cortical spreading depression”. Most people have a good idea of what epilepsy is, a lot of very fast brain activity leading to strange symptoms. Well, cortical spreading depression is kind of the opposite. Instead of a lot of big, fast brain activity, it is a slowing of electrical activity in certain areas of the brain. This is what leads to some of the strangest migraine symptoms out there. 

Most people have heard of the sparkling lights or zig zag lines of a migraine aura. However, most people don’t know the half of it. Other people see glowing orbs in rainbow coloring. Some people have visual distortions like everything is in a funhouse mirror. Some migraineurs experience “Alice in Wonderland Syndrome” where things they are looking at grow to enormous sizes or shrink down very small. One of the most disturbing is prosopometamorphopsia, where a migraineur is looking at someone’s face and it starts changing into something. I had a patient whose mother’s face turned into the head of a dragon and breathed fire at her. She was pretty convinced she was developing schizophrenia until I explained it was a well documented symptom of migraine. 

However, the most common and worrisome symptom of migraine is often dizziness. Dizziness is pretty complicated. You get a lot of sensory input that your brain needs to integrate to keep the world seeming still. Your vision, signals from your inner ear, signals from your neck muscles, and signals from the rest of your body all have to line up perfectly or else the world begins to turn on its axis. If untreated, this can lead to constant and debilitating nausea, imbalance, and falling. At times, the dizziness only occurs during migraine headache attacks, but for some migraineurs it becomes constant. At times, migraine meds can help, but often a specialized form of physical therapy called vestibular therapy is required. Even with treatment, migraineurs often can’t stand to ride in the back seat of a car or they get severely ill. The mismatch between their vision and their vestibular system is enough to cause pretty remarkable motion sickness. Unfortunately, there isn’t a good medicine to help this dizziness. Most of my patients are started on Meclizine, but it just sedates them and doesn’t allow the brain to recalibrate. When I meet a nice older migraineur who has been on meclizine three times a day for a few years, I know there is a steep uphill battle ahead to give them relief. 

So now that we’ve discussed the common symptoms, or basics of migraine, feel free to look at more articles about specific consequences of “cortical spreading depression” and other consequences of “Central Sensitization” in chronic pain. You can also request a consult today to discuss your symptoms and possible treatment options.