What Really Happens To Your Body When You Get A Migraine

Migraines impact millions of people worldwide, and chances are good that you suffer from them yourself or know someone who does. Those who have never experienced the pulsating pain, the nausea, and the debilitating sensitivity might find it next to impossible to truly understand what sufferers are going through. According to the Migraine Research Foundation, it's now classified as a neurological disorder that's the sixth most disabling disease in the world.

Migraines present themselves in a myriad of ways, with people experiencing different combinations of triggers, symptoms, and even after-effects. That's made it incredibly difficult to determine just what causes migraines, how to prevent them, and even what goes on during this crippling, painful headache. There's no cure for migraines, and no cause that's completely understood yet. That said, we do know some of what goes on in the body and brain during a migraine. Understanding that might help you take extra steps to managing triggers, symptoms, and occurrences, and any step in the right direction is a welcome one.

Technically, a migraine begins long before you even start to feel that telltale pain, and researchers have found that most people develop particular tells that are your body's way of foreshadow the coming migraine. Identifying them is tricky, though, as different people develop different signs that can include almost anything and everything, from excessive yawning to tense muscles and even cravings for certain types of food. These strange signs can develop anywhere from a few hours before onset to a few days, and no one's completely sure just what's going on here. Neurologists from the University of California-San Francisco are hoping that decoding the cryptic warning stage can help unlock other secrets that are going on in the brains of migraine sufferers, but it's an incredibly challenging thing to study.

Since the symptoms are so unpredictable and vary so much from person to person, the changes that the entire body seems to go through are only vaguely known. One of those changes seems to be a slowing of the digestive system, as people who report vomiting as one of their symptoms also report that what they're getting sick on is food they ate a day ago. Normally, that would be long digested, but the implications that migraines are impacting the way our bodies function that far in advance is pretty mind-blowing.

It's also thought that this stage implies some triggers are misunderstood. Say, for example, you get migraines after you eat a chocolate bar. You might think that chocolate is your trigger, but those same neuroscientists encourage you to look at why you ate it in the first place. Was it a craving? If so, that chocolate could be a symptom, not a trigger, and you're actually feeling this premonitory stage.

About a third of the people who suffer from migraines develop what's called an aura. Typically, the aura manifests as lines that cross your vision, blurry patches, or, for some, it means losing parts of your vision altogether. Since most migraines impact your sight but not all are considered migraines with auras, the difference is an important one. Think of a blistering, boiling parking lot on a hot, sunny day. Those wavy, hazy lines that you see? That's what an aura can look like.

Neuroscientists from the University of California-San Francisco took a look at what's going on in the brain of a person who's suffering from a migraine with an aura and found something amazing. The cerebral cortex is the part of the brain that's gray matter, and it's responsible for everything from receiving sensory input to coordinating our movements. Researchers found that during the aura phase of a migraine, electrical pulses sweep across the cortex over and over. As the pulse goes through the brain, it activates nerve cells in what's called cortical spreading depression, and we feel the corresponding pains. When the pulse hits the part of the brain that governs your sense of touch, your skin tingles. When it hits your visual control centers, you see the lines. Once the electrical waves stop, the aura goes away.

First, a bit about the basics. If you suffer from migraines, this should sound at least partially familiar, while if you only know someone who gets them, this might help clear up just what's going on. The pain phase of the migraine is characterized by things like a sensitivity to light and touch, a searing but localized pain, pulsing pain, sweating, clammy skin, nausea and vomiting. Not everyone develops all the symptoms, and some people may even start slurring their speech, experiencing temporary blind spots, and feeling a spreading numbness.

Scientists are only starting to figure out what's going on to cause all that, and it's thought that the underlying cause is an increased sensitivity to certain stimuli, called triggers. Everyone has different triggers (which also makes the science stuff difficult), but those triggers seem to activate something called the trigeminal nerve, which sends information received by the surface of your face into your brain. Migraine sufferers have extra-sensitive nerves and sometimes, that nerve goes into overdrive and releases extra chemicals into the brain, which then causes the inflammation of blood vessels.

Those inflamed blood vessels essentially create a sort of panic in the physiology of your brain, causing your migraine symptoms. The brain stem is flooded with serotonin, electrical activity increases, and blood flow through the brain changes drastically. It decreases in the part of the brain that governs sight (called the occipital lobe), which could explain why sensitivity to light is such a common symptom. The pulsing pain comes from those same inflamed blood vessels as surges are pushed through your brain at an abnormal rate. These changes can last hours, creating enough havoc that effects of the migraine can last much, much longer than the physical changes that happen in the brain.

The diversity of symptoms and the different ways each individual person can experience a migraine means there's a lot that remains stubbornly unknown. Perhaps most unknown of all is the postdrome phase, which has only been really acknowledged since 2004, and remains vastly understudied. There's a few reasons for this, and the first is that this is the part of the migraine where the worst of your headache has gone away, and you're feeling not entirely better, but at least not in agonizing pain. For a long time, there was just no point in studying that, but now researchers are starting to realize that the varying symptoms of the postdrome can be a part of the migraine for some sufferers.

In 2016, a study published in the journal Neurology estimated that around 89% of migraine sufferers went through a postdrome phase. They haven't gotten too much closer to figuring out just what's going on in the bodies and brains of those that do report this phase, though, and the symptom list is pretty extensive.

It varies, but people report feeling things like fatigue, dull aches, weakness, a complete lack of energy, dizziness, difficulty concentrating and thinking, mood changes, and a lack of desire to do much of anything. People can report all, none, or part of these symptoms, and the really strange part? There seem to be no physical or biological markers that indicate someone is going to develop postdrome symptoms, or any telltale signs that there's anything different going on in them as they experience this phase. That's in spite of the fact that the overwhelming majority of sufferers report post-headache symptoms, which has left the science world shaking its collective head in confusion.

It seems like it should be a straightforward thing. You're exposed to a trigger, and that sets you on the path to a full-blown migraine. While some people might be able to figure out that drinking a certain type of wine might trigger a migraine, it's way more complicated than that for most.

In 2013, neurologists at Wake Forest Baptist Medical Center took a look at what most people described as triggers, and traced how outside encounters provided potentially triggering stimuli to migraine sufferers. They found a huge number of variables that made it next to impossible to tell just what was going to set off a migraine response. Say, for example, you can count on a migraine that's triggered by the start of your period. That comes along with cramps, so you always have a glass of red wine to try to relax those muscles. Is it the red wine, or the period that's triggering your headaches? Maybe you love white wine, but it sometimes seems to give you migraines. Sometimes you can have a glass and be fine, but a couple nights later? Migraine. Is it the wine, or the night that you skipped a glass that's causing your migraine?

The truth is that no one's really sure how factors come together to set off a migraine. Neuroscientists think that something that might seem insignificant can cause (or prevent) triggers from turning into full-blown migraines, and that can include things like weather or air pressure, how much sleep you've gotten recently, and how much stress you're under. Identifying triggers can help you prevent future migraines, and some people can only do that by keeping a detailed diary and recording not just things like what you had to eat, but what's going on in your body every day. Write down things like exercise, sleep times, and stress, as that can all be tied to what's going on in your brain.

One of the biggest symptoms of a full-blown migraine is sensitivity to light, and it can also be a trigger. In order to try to find out just why that's such a major part of migraines for so many people, researchers from Harvard took a look at what was going on when two groups of people, all blind, suffered from migraines.

One group was made up of people who were completely blind due to various types of diseases and disorders of the eye, while the other group suffered from degenerative diseases and were only considered legally blind. The first group could detect no light at all (and couldn't use the presence of it to govern their sleep cycles), while the second group could. When they exposed the first group to light that triggered sensitivity in sighted suffers, none reported that their migraines got any worse. The second group reported an increase in pain, and that helped to narrow down just what was going on in their brains. The optic nerve is what gives your brain signals regarding light, and it was only the patients that had intact optic nerves who described the sensitivity to light.

They were particularly sensitive to blue and gray light, and that suggests it's even low-light situations that can cause an increase in migraine pain. When researchers experimented on rats, they found that their optic nerves took signals straight into brain centers that were pulsing with electrical activity during migraines, giving considerable amount of credence to the idea that retreating to a dark place really does help relieve pain and migraine pressure.

The idea sounds pretty terrifying, and the truth is, scientists aren't exactly sure just what's going on in the brains of migraine sufferers and whether or not any of the observed changes do have long-term or detrimental effects. They do know, though, that migraines seem to cause the development of lesions (or small patches of dead tissue) in the brain's white matter.

White matter is the part of the brain that enables the different parts to communicate with each other, and MRI scans of people who suffer from migraines tend to show the development of what's technically called white matter hyperintensities, or WMH. The more often migraines occur, the more completely they develop, and they also seem to be more common in those that experience auras with their headaches. That being said, the development of brain lesions might seem like a terrifying thing, but medical professionals say that it's perfectly normal. There are no symptoms or issues associated with WMHs, and migraines aren't the only things that cause them, either. Alzheimer's patients also show the development of WMH and, in some cases, it's simply linked with age.

Occasionally, some migraine sufferers seem to develop what's called infarct-like lesions. These lesions are something a bit different, and according to researchers from the Montefiore Headache Center in New York, these lesions can be something serious. They develop in the brain like tiny, tiny strokes, and may mean that those who have these lesions will ultimately be at a higher risk for a larger stroke later. (They also stress that just because you have regular migraines, that doesn't mean you're going to ultimately have a stroke, but they do suggest that migraine sufferers take extra care to lower other things associated with stroke risk, like bad cholesterol.)

It's only relatively recently that scientists have also started looking at a possible connection among estrogen, female hormones, and migraines. Women are more likely to suffer from migraines than men, and for many girls, their first one happens during puberty. Migraine instances spike around the ages of 13 and 17, and by this time the ratio of female to male sufferers rises to around 3:1. Instances of migraines usually decrease around the time of menopause, and all that seems to point to the idea that estrogen plays some sort of critical role in what's going on.

A recent study from Johns Hopkins and the Carolina Headache Institute took a look at 18 months worth of data drawn from other scientific migraine studies that gathered data from 160,000 participants. Comparing the MRIs of female participants to males showed consistent differences in the way women's brains reacted to the onset of migraines and to stimuli that happened during the headache. They also found that the extreme fluctuation of estrogen levels throughout a woman's lifetime likely play a role in the development of migraines, as it can directly influence the brain through estrogen receptors in the nervous system and the brain itself. They also found that women who experience migraines in conjunction with their menstrual cycle generally developed their headaches when their estrogen levels declined. For some women, taking birth control pills can help regulate migraines. The implications are pretty staggering and suggest that regulating estrogen levels might help to prevent headaches. That's all exciting news for migraine sufferers, but they also say that this is likely just one more piece in what's an incredibly complicated puzzle.