The first time it happened, or the first time I can remember it happening, was in 1978, when I was nine. I was on holiday in the Loire valley with my mother, my stepfather and my brother. It was a holiday of firsts: my first trip abroad; my first snails and proper yoghurt; my first fizzy mineral water. It was also the occasion of my first full-blown migraine attack - which perhaps is why all these other details are still so clear to me. On the night in question, we were staying in a small creeper-covered hotel in a town called Bléré. The day had been spent visiting the requisite château, where we had a roadside picnic of bread, soft cheese and jam, after which we had come back to the hotel for a siesta: we would be eating a lot later than we did at home in Sheffield. But I had not been able to sleep - what was the point of sleeping in the day, when the sun was still shining? - and the afternoon had passed agonisingly slowly. I was glad that we would soon be going down. In fact, I could hardly wait. Even then I was greedy. I was wearing a denim skirt my mother had made me, and a polo neck the colour of salmon lipstick. I thought it very fetching.

It started in the final tantalising hour before dinner: the pain in my head. At first it wasn't too bad. It throbbed, but if I was careful, and avoided looking directly into the light, and held my head at a certain angle, I could just about bear it. So I sat very still, and I waited, hoping it would shift by the time my mother came to our room to get us. But it didn't shift. It was getting very much worse. It was starting to make me feel sick. When my mother arrived, she looked at me - knowing what I know now, I must have been completely grey - and asked if I was OK. I said: "I've just got a bit of a headache." I played it down because no one likes a killjoy, and also because I had got my salmon sweater on, and I was damned if I was not going to have that lovely long menu haltingly explained to me while some waiter looked on admiringly. So she gave me a soluble aspirin - my mother always had soluble aspirin to hand - and I drank it down, and hoped it would work especially quickly. I remember, vividly, the feeling of gathering myself. I was only nine, yet I was contemplating the hours ahead in the same way that an arthritic old lady contemplates a set of stairs. How were they to be negotiated without some terrible crisis of pain?

After this, my memory grows more hazy.

I think that I managed to eat a starter before it became obvious to me, and to the rest of my family, that I could not remain at supper. Behind my right eye, something was going on: something terrible. It was as if someone was beating me with a poker, except that the person perpetrating this frenzied attack was inside my skull, trying to bash their way out. The pain seemed to have taken control of me. I could hardly see; I could hardly talk; I could hardly move. It had rendered me entirely abject. Who cared what anyone thought now? If I had been able, I would have crawled under the dining table and tried to go to sleep then and there, curled and clammy: anything rather than to have to make the nauseous journey back to my bedroom. My mother, though, could see what was on the horizon, which was a fiesta of vomiting. So she led me out, a guide through the dark tunnel, and put me to bed, and for the next few hours, while the three of them ate rillettes de porc and confit de canard and the finest camembert, I lay in bed as still as stone, my torture punctuated only by pathetic crawls to the lavatory, where I would lay my aching head on the edge of the bowl and enjoy the fleeting relief afforded by extremely violent puking. "That no one dies of migraine seems, to someone deep into an attack, an ambiguous blessing," writes Joan Didion in her essay "In Bed". Aged nine, I had neither heard of Didion nor read her essay. But I already understood the sentiment. "You'll feel better in the morning," said my mother, when she came up to bed. This was not comforting. How was I expected to last that long?

So I have had migraines since I was nine years old, though my mother thinks that it really began even earlier, in the form of unusual and unexplained stomach upsets (childhood migraine often manifests itself this way at first). I feel strange about telling you this because I don't want you to think that I am some odd and feeble Elizabeth Barrett Browning figure who spends days at a time prone on a chaise longue, waiting for her latest attack of the vapours to pass. Then again, thinking about this piece, and researching it, has reinforced the position I have always held so far as my own migraine goes. I am not mad, nor are my symptoms psychosomatic. The World Health Organisation, no less, has recently described migraine as one of the four most disabling chronic medical disorders. At a conservative estimate, migraine affects between 10% and 12% of the population at some point; in the UK, this amounts to 6 million people. I am not, then, alone even if, when I am in the middle of an attack, it often feels that way. Among the more famous migraineurs are Vincent van Gogh, Virginia Woolf, Elvis Presley, Lewis Carroll, Julius Caesar, Emily Dickinson and Sigmund Freud. Not bad company to keep, though I would be happy hanging out with Frederick Forsyth and Jordan if this meant that I no longer got headaches.

By the standards of many migraineurs, I am lucky. I have about six attacks a year, at most. When Joan Didion was writing in 1968, she was losing four days a week to her headache.

Ten per cent of sufferers get them weekly, and 14% more than 15 days a month. Still, when they come, they are shockingly bad. A migraine is not just another stress headache; it is utterly debilitating. When one catches me, unprepared, in a public place, it is also utterly humiliating, except that the pain is so cruel you only feel humiliated afterwards; at the time you could not care less if someone has mistaken you for a drunk.

The worst attack I ever had - both in terms of pain, and humiliation - occurred four years ago. I was trying to leave Israel, where I'd been working. Unfortunately a small white lie that I had told to ease my passage through security ended with me being strip searched, and very late for the plane. Lots of things trigger a migraine, almost always in combination, and this debacle was a perfect storm for my poor little brain: a lack of sleep through an early start; an absence of breakfast, or anything else to eat, which had led to a rapidly falling level of blood sugar; the stress of the security process; the air-conditioned atmosphere of the airport.

I tried to tell the girl who was searching me that I needed to have something to eat and drink - anything - as a matter of urgency. But, no joy. By the time I got on the plane I was in agony. By the time the plane was in the air I was vomiting uncontrollably in my seat, a real mess. The man next to me looked appalled, though he didn't bother to ask if I was OK. I arrived in London, swaying and sticky, somehow negotiated passport control, and then I lay on a bench in baggage reclaim looking for all the world like a disgraceful junkie. My hair was matted. I stank.

I could barely form a coherent sentence. And then, suddenly, there was light. The migraine lifted. I went into WH Smith, where I bought a can of Coke and some fruit pastilles - in post-migraine euphoria I crave sugar like you would not believe - and then I made my way home.

I was as frail as glass, but I was better.

It is generally agreed that by the time the full pain of a migraine kicks in, you have already been suffering from an attack for a while, perhaps for up to 24 hours. In this period, before the crisis, most people have premonitory symptoms: a sign of what is ahead. The most famous of these is the "aura": a collection of visual symptoms that can include blind spots, a difficulty in focusing and flashing lights. Only rarely do I have an aura. Other premonitory symptoms are mood changes (you feel high or, more often, low); lethargy and clumsiness; gut problems such as constipation; a craving for certain, often sweet, foods (this is why many people mistakenly believe their migraine to be triggered by chocolate). My most significant symptom is compulsive yawning; in the hours before my headaches, I yawn every 10 seconds. At Ben Gurion airport, in Tel Aviv, I was yawning about every five seconds. Until very recently, I thought this was unique to me. It seemed so... bizarre. Then I went to interview Siri Hustvedt, the novelist and a fellow migraineur. We talked about our headaches. "Do you get that yawning thing?" she said. A light bulb came on over my head. "Yes. God. I really do." She laughed. "Me too," she said. "Isn't it crazy?"

Most doctors agree that migraine has a genetic component. Does this mean that there is also such a thing as a migraine personality? I looked at Hustvedt, so intense, so clever and so pale, and I wondered. In 1963 a doctor called HG Wolff characterised migraineurs as: ambitious, successful, perfectionistic, rigid, orderly, cautious, emotionally constipated, and driven. Joan Didion writes that while "not all perfectionists have migraine, and not all migrainous people have migraine personalities", she thought that her own perfectionism - which takes "the form of spending most of a week writing and rewriting and not writing a single paragraph" - might have something to do with it, at least. But the neurologist Oliver Sacks, author of a classic text about migraine, disagrees: "Patients with severe habitual migraine seemed to me to be so various in their emotional pathologies and predicaments that I despaired of putting them in a single category."

What do I think about this? I think that it would be nice, if a little self-aggrandising, to see myself as belonging to this special group of successful people (and it is certainly true that I am a perfectionist). But I am also wary of connecting pain to personality. It seems too 19th century to me, too madwoman in the attic (two-thirds of migraine cases occur in women). Hustvedt told me that after fighting her migraine for years, she had decided to accept it as a part of her. Perhaps she needed it in some way; maybe it was her body's way of telling her to stop. And some clinicians agree with this notion, to a degree. "We always make the presumption that because migraine is so unpleasant, it must be doing some harm," says Dr Anne MacGregor, director of research at the City of London Migraine Clinic. "But you could equally argue that it is protecting the brain from too much stimulation; it's like a circuit breaker." But I am unconvinced. I need it like I need a hole in the head. Which is exactly what it feels like, most of the time.

I'd far rather blame it on modern life, which is rubbish. Or it is for the migraineur - and this, perhaps, is why the incidence of migraine appears to be on the rise, if not the number of sufferers (those prone to migraine are enduring more attacks, a trend that possibly explains why there are now 600,000 migraine blogs on the internet). Migraine hates routine, and modern life is not exactly conducive to routine. Migraine sufferers must eat regularly, exercise regularly and sleep for the same number of hours every night, getting up at the same time each day (a lie-in can cause havoc for the migraineur, hence the phenomenon of the weekend migraine, when the patient only ever has an attack on Saturdays). Flickering computer screens don't help either, and on that score things could be about to get worse.

In 2008 the government decreed that incan descent light bulbs would be phased out and replaced by energy-efficient equivalents (compact fluorescent light bulbs). Large retailers no longer sell the old 100 watt bulbs. By January 2010, 60 watt bulbs will have disappeared; by December 2011, 40 watt bulbs will be gone, too. But energy-saving light bulbs can trigger migraine, either as a result of their flickering (the technology they use is similar to that of fluorescent strip lights), or the low intensity of the light they emit. The Migraine Trust has recently submitted research on this area to the Department of Health; it would like migraineurs to be able to use traditional bulbs until the problem with green bulbs is fixed. I can only be anecdotal about this. The other night I went to dinner at a house where all the bulbs were "green".

I noticed the uncomfortable quality of the light immediately. Twenty-four hours later I had my first migraine in three months.

In ancient Greece, Galen attributed migraines to the ascent of humours from the liver to the head. He called the condition hemicrania - a painful disorder affecting half the head - a word that eventually became "megrim" and, finally, migraine. More than 1,800 years later we still don't precisely understand the causes of migraine - though we are getting closer. According to a recent paper in Scientific American, the condition is now thought to arise from a disorder of the nervous system - and from the most ancient part of that system, the brain stem. Migraineurs' brains are hyperexcitable (this sensitivity may be genetically determined), meaning that they are much more sensitive to stimuli than someone not prone to migraine. During an attack, blood flow to the brain increases by about 300%. This results in cortical-spreading depression, a wave of intense nerve cell activity that spreads through a large swath of the cortex (the outer layer of the brain). This may cause both the aura and the pain. But the science involved is highly complex, and still controversial. Researchers are, however, now testing drugs that specifically inhibit cortical-spreading depression, a move that could ultimately lead to a very significant breakthrough.

In an interview the novelist Zoë Heller once said that the one thing that would improve her life was a cure for migraine. Will we ever get to that stage? "I don't think we'll ever get to the point where we can say: your body is never going to be capable of having a migraine," says MacGregor. "It would be like saying: your body is never going to be capable of experiencing pain. We think about control rather than cure. The issue is: who is in charge? Is your migraine controlling you, or are you controlling it?" Of course knowing your triggers, and avoiding them, helps a lot - though given that these can include almost everything, from drinking wine to the smell of a certain perfume to your menstrual cycle, this is not always as easy as it sounds. Beyond this, most of us rely on a group of drugs called the triptans, one of which, sumatriptan, can now be bought over the counter in the form of a pill called Imigran. A triptan taken as soon as your headache starts can be very effective, aborting an attack within 30 to 90 minutes. Here's a thing, though: doctors are not sure how, exactly, they work (they were developed to treat other diseases). Is it just that they constrict the blood vessels in the brain that become swollen during an attack? Perhaps.

The arrival of Imigran in Boots in 2006 was wonderful for me. It is a serious drug, and I try not to take it too often. But knowing that I can get it without the palaver of a doctor's appointment, and having it in my bag when I am travelling somewhere inhospitable - a place where it would really not be a very good idea for me to lie down in public - is an immense comfort.

I am, though, expert at self-treatment. If I have a hot shower - as hot as I can bear - early on in an attack, I can sometimes send it on its way.

I also know the arc of my migraines well enough now to be able to accommodate them. I know how long they will last. I know that once the vomiting starts, I am almost home and dry; these days, the vomiting almost comes as a relief.

Have I tried the sillier things? Ha. It will not surprise you to know that I'm unconvinced by things like acupuncture: I want drugs, and I want them now! But I do own a few of the barmier bits of headache hardware you can find; I bought them while I was thinking about this piece. The Migra-Cap, which you keep in the fridge and which, once it is on your head, makes you look like an inmate of Guantánamo Bay, combines cold therapy with darkness and is endorsed by the cricketer Mark Butcher, another sufferer.

But it doesn't do it for me. Like I say, I need heat. I also have a Rio Light Mask, allegedly trialled by doctors at Hammersmith Hospital, which uses "photic stimulation in the form of programmed patterns of gently pulsating light" to prevent migraine. I have no idea if this works. I used it and I didn't get a migraine. But then I might not have had one anyway. Also, you're supposed to wear it at bedtime. It does not exactly - how to put this? - encourage conjugal intimacy.

Anyway, I have outed myself now. Migraineur. Feeble woman. There it is. Except I have always felt that my migraines, and the sensitivities in my brain that they betray, have made me, if not more special, then certainly more strong. Whatever else they've done for me in my life, they have turned me into a stoic, a survivor, into someone who can get through. In the middle of an attack, I will tell myself this: You can get through. And, of course, I always do. And the hours afterwards bring their own rewards: the intense happiness that comes with feeling better; the way that the world, seen through convalescent eyes, is so immaculate and finely drawn and full of promise; the way that I'm suddenly so intensely productive; the way that food and drink and - I might as well be honest - Rowntree's Fruit Pastilles suddenly taste so very good. I await the next generation of drugs impatiently; I'd be lying if I said otherwise. But in the meantime,

I can probably cope - compact fluorescent light bulbs allowing.