Splitting - headaches 101

To give us an overview on headaches, Durham University neuroscientist Amanda Ellison has just written a book on exactly this. Amanda told Katie Haylor that headaches allow us a window into better understanding how the brain works in concert with the rest of the body. Firstly, Amanda and Katie discussed some of the different types of headaches that we might come across...

Amanda - There are lots and lots of classifications of headaches. And depending on which classification you look at, you will see that there are headaches and subtypes of headaches and... it's enough to give you a headache! So really what I focused on in this book is five main types of headaches. So we begin our story with brain freeze headache - that, actually more scientifically, is called cold stimulus headache. And lots of us have experienced this, that stabbing pain in your temple when you've gobbled your ice cream too fast, or had a smoothie or something like that. We talk about that and what it is that's going on there.

Then we talk about sinus headache, which is really quite prevalent also, and undervalued, I think, by people, in terms of how pervasive that kind of headache is. It's oftentimes always there. Sinus headache is born out of congestion in your sinuses, hollows in your bones. But sometimes they get very clogged up with mucus and the mucus is there to flush out any bugs or allergens that are in there. Obviously people who deal with allergies every year, they're very used to this, and sometimes these allergies will build up the mucus and then will trap other nasty things like bacteria or viruses inside the sinuses and they find it very, very hard to escape. And so it's inflammation upon inflammation upon inflammation, as your immune response tries to flush out these bugs. And the problem with that then is that your head feels very congested. And it sets off the same kinds of reactions that you get in any other kinds of headaches. You get vasodilation, you get activation of the main pain receptor in the head, which is the trigeminal nerve. All of this is interpreted in your brain as pain, and it actually manifests as a pain in your face and a pain towards the front of your head. So it really feels like you've been hit in the face with a spade.

Katie - Okay. So brain freeze - don't eat your ice cream too fast. Sinus headaches - I think I know the kind of painful pressure build up that you're talking about. Am I on the right lines?

Amanda - Absolutely.

Katie - What are the other three?

Amanda - Tension headache is really, really common. And it's also known as the stress headache, and it is born out of emotional stress, sure, because when we are stressed emotionally, or we've got lots of things going on, you do very much feel stressed and you feel emotionally stressed, but your body actually becomes stressed too. You hold yourself in a different way. Your back is more tense. Your posture is worse. You're possibly rushing around from place to place or exerting energy that you wouldn't ordinarily be exerting. And this will all feed back up to your brain. And if your body feels tense, you feel emotionally tense. Then that doesn't help. Your brain feels like it's under attack. It is very much the fight or flight response.

Originally, it's a very adrenaline based response and that creates the energy in order for us to deal with the problem that we're trying to deal with in front of us. Over the longer term - cortisol, we're talking about a heightened response to stress. This causes generalised inflammation. It also causes an immune response. It causes release of things like nitric oxide that cause vasodilation. And again, now we're getting into the situation where we realise all of these resources come in to the brain to allow us to deal with the problem that's in front of us. It's causing vasodilation of the cerebrovascular system. And that's triggering off the pain receptors in the head, that's says "Danger! Danger! These blood vessels might not be able to take this for much longer".

Katie - Tell me about migraines because I'm certain they're going to be on your list. I think I've had two migraines in my life and honestly, they were absolutely horrendous. I remember feeling sick. I cried a little bit. My head felt like it was going to explode. And the only thing I could do was jump under my bed and try and block out any sensory stimulation until it went away. And if I ever hear someone now saying, "Oh, I think maybe I've had a bit of a migraine the other day", I think, "Did you?" Is that fair?

Amanda - That's entirely fair Katie, yeah. It's terrible. Because when you write a book like this and I've been involved in this field for a long time and it really does make you second guess your fellow man, and woman, because when they do say, "Oh, I had a touch of a migraine. You're like, "no, you don't get a touch of migraine. You either get migraine or you do not." And it's very much along the lines of, "I had a touch of the flu". No, you didn't. You had a cold, it might have been a bad cold, but that was not influenza. And if it was the flu, you would know all about it because flu is an entirely different animal. And it's the same kind of thing with migraine. Not all bad headaches are migraine.

Katie - What is going on that makes a migraine so horrendous?

Amanda - You actually have four stages to it. You have the prodrome phase, which is happening before you even know it's happening. And this is when various things are happening across the cortex of your brain. You're getting waves of excitation, followed by waves of relative inactivity. And this then changes the balance of neurochemicals in your brain. It starts to create a pain-type response. That's all part of the aura phase. Now some people experience an aura, which is a visual or sensory disturbance, and some people do not. But we think now that actually the same thing that's happening in the brain, whether or not you are experiencing the aura. Whether or not you experienced the aura is based on how eloquent your cortex is. So if your cortex is very eloquent, you will experience it as a sensory disturbance. But if it's not very eloquent, well it's happening anyway. And then that then sets up your pain phase. And that's when you get this deep throbbing in parts of your head, usually towards the front, usually on one side, at least initially, and it can be a really horrendous pain. It feels like somebody's just trying to crack your skull open. And you can actually get some really bad sensory disturbances with that as well, because what's happening inside your cortex feeds into your subcortical structures. And they're the things that's do all the things you're not aware of. So breathing, thirst, how hot and cold you feel, your temperature regulation, nausea. All of those different things. And that keeps coming in waves and waves. And that explains how crummy you feel. And it really does knock you flat.

And even after that, then you have the postdrome phase where everything is trying to get back to normal inside your brain. You feel mentally unable to add two and two together because who cares? And you just really have a hard time getting back on your feet. And that's as everything resets. You really do need to just take yourself away to a dark room, and let it all just take its course, unless you take any kind of medication to intervene with migraine. And that really is your body incapacitating you to allow everything to reset to normal.

Katie - In the book, you mentioned cluster headache. And I'm wondering if perhaps this might be number five on your list. You mentioned a man who was out of it for two weeks with a cluster headache! What on Earth is it?

Amanda - Yeah, cluster headache is the strongest headache. It's the one that has been rated as being the worst headache that you can ever get. I've had some experience in witnessing this myself, thankfully, I've never experienced it to my knowledge. I did witness somebody banging their head against the wall with this particular type of headache. It goes back to taking that person out of life and society until what's happening in their brain settles down. And that can take weeks for certain people, particularly if they've missed a particularly small window that they have in order to intervene with this headache.

Now with cluster headache, the name comes from these headaches happening in clusters. So they can happen over the course of a day, or over the course of weeks, or over the course of months. But generally they will be diagnosed if you have five episodes of that separated by remission phases. And they are really, really debilitating. They feel like somebody's trying to force your eye out from the inside. It's horrendous and, and there are various other things that people report, like they have a droopy eye, they're tearing up on one side of their face, it's almost like the paralysed as well. There are lots and lots of different effects of this and people just feel generally awful.

Katie - Is there any way of predicting when this is going to happen? Are there some people who are a bit more sensitive? It just sounds so debilitating. Are there ways of controlling how this comes about?

Amanda - There are absolutely ways of controlling how this comes about. But I think what it requires is a good understanding of A) which type of headache it is that you're prone to. It's very important to identify the kinds of headache that you have. The second thing that you need to do is to think about your body and your life and see how it is that that is impacting on your headache. I say this all the time. With headache, prevention is better than cure, but you've got to understand how you as an individual can prevent the headache for you. We all have different pain thresholds. You actually do have a whole other part of your brain, which we now know is very much involved in our own perception of pain. We also need to then understand where these headaches come from and how that intersects with our lives. Now for tension headaches it's easy to point out "well, you know, you've got posture, you've got dehydration, you've got stress". You've got all of these things that are the umbrella terms that explains it.

But for something like migraine or something like cluster headache, there are things that you can do to make sure that you don't expose yourself to any triggers that are peculiar to you. It's easier in migraine to a degree than with cluster headache, because with cluster headache, we seem to think it has a lot to do with the subcortical regions of our brain and things that are happening automatically. And there are certain things that we cannot control there, like the light that's coming into our eyes and various aspects like that. But with migraine, there's been so many urban myths that have grown up around this. So one of the things I did in the book was try to go through all of that and say, "right, what does it mean from a scientific point of view? What's the literature behind this? What's the evidence behind this?"

Katie - What do you think about the public profile of headaches? Do you think we take them seriously enough? Because a lot of this interview has been pretty heavy going in terms of talking about an awful lot of pain. And sometimes if someone was just to say to me, "I've got a bit of a headache". I probably wouldn't actually take it that seriously.

Amanda - There's an element whereby it isn't taken seriously enough. You have a colleague who says, "I have a bit of a headache" and you say, "well, I've had one for six years and I'm getting on with it". And it's very much dismissed as something that almost you're perceived as being weak if you admit to having a headache. But actually headaches tell us a lot about what's happening inside of our bodies. And we, as individuals, should take them seriously.