Patterns

I have had migraines for most of my life; the first attack I remember occurred when I was 3 or 4 years old. I was playing in the garden when a brilliant, shimmering light appeared to my left — dazzlingly bright, almost as bright as the sun. It expanded, becoming an enormous shimmering semicircle stretching from the ground to the sky, with sharp zigzagging borders and brilliant blue and orange colors. Then, behind the brightness, came a blindness, an emptiness in my field of vision, and soon I could see almost nothing on my left side. I was terrified — what was happening? My sight returned to normal in a few minutes, but these were the longest minutes I had ever experienced.

I told my mother what had happened, and she explained to me that what I had had was a migraine — she was a doctor, and she, too, was a migraineur. It was a “visual migraine,” she said, or a migraine “aura.” The zigzag shape, she would later tell me, resembled that of medieval forts, and was sometimes called a “fortification pattern.” Many people, she explained, would get a terrible headache after seeing such a “fortification” — but, if I were lucky, I would be one of those who got only the aura, without the headache.

I was lucky here, and lucky, too, to have a mother who could reassure me that everything would be back to normal within a few minutes, and with whom, as I got older, I could share my migraine experiences. She explained that auras like mine were due to a sort of disturbance like a wave passing across the visual parts of the brain. A similar “wave” might pass over other parts of the brain, she said, so one might get a strange feeling on one side of the body, or experience a funny smell, or find oneself temporarily unable to speak. A migraine might affect one’s perception of color, or depth, or movement, might make the whole visual world unintelligible for a few minutes. Then, if one were unlucky, the rest of the migraine might follow: violent headaches, often on one side, vomiting, painful sensitivity to light and noise, abdominal disturbances, and a host of other symptoms.

In her memoir, “Giving Up the Ghost,” the British novelist Hilary Mantel describes the migraines she started to have in early childhood:

My eyes are drawn to a spot. … I can’t see anything, not exactly see: except the faintest movement, a ripple, a disturbance of the air. I can sense a spiral, a lazy buzzing swirl, like flies; but it is not flies. There is nothing to see. There is nothing to smell. There is nothing to hear. But its motion, its insolent shift, makes my stomach heave. I can sense — at the periphery, the limit of all my senses — the dimensions of the creature. It is as high as a child of two. Its depth is a foot, fifteen inches. …. It has no edges, no mass, no dimension, no shape except the formless; it moves. …. Within the space of a thought it is inside me, and has set up a sick resonance within my bones and in all the cavities of my body.

For Mantel, as a child, migraine “charged [the air] with invisible presences and the echoes of strangers’ voices; it gave me morbid visions.” She writes:

Sometimes the aura takes more trying forms. I will go deaf. The words I try to write end up as other words. I will suffer strange dreams, from which I wake with hallucinations of taste. …. A tune will lodge in my head like a tic, and bring the words tripping in with it. … It’s a familiar complaint, to have tune you can’t get out of your head. But for most people the tunes aren’t the prelude to a day of hearty vomiting.

For a time, as a child, Mantel saw “a constant, moving backdrop of tiny skulls … skulls skulls skulls, the size of my little fingernail, unrolling … like a satanist’s wallpaper.”

Seeing multitudes of tiny, identical structures, sometimes “unrolling” steadily, sometimes flickering, forming and reforming, all over the visual field, is common in migraine auras, though it is only occasionally that these are elaborated into tiny skulls, or arrays of faces or animals or other objects.

A 16th century Turkish Anatolian carpet. (Credit: Peter DaSilva for The New York Times)

In my own migraine auras, I would sometimes see — vividly with closed eyes, more faintly and transparently if I kept my eyes open — tiny branching lines, like twigs, or geometrical structures covering the entire visual field: lattices, checkerboards, cobwebs, and honeycombs. Sometimes there were more elaborate patterns, like Turkish carpets or complex mosaics; sometimes I saw scrolls and spirals, swirls and eddies; sometimes three-dimensional shapes like tiny pine cones or sea urchins.

Such patterns, I found, were not peculiar to me, and years later, when I worked in a migraine clinic, I discovered that many of my patients habitually saw such patterns. And when I looked back on historical accounts, I found that Sir John Herschel, the astronomer, had given detailed descriptions of his own visual migraines in the 1850s. He wrote to his fellow astronomer and fellow migraineur, George Airy, quoting his own notes: “The fortification pattern twice in my eyes today …. Also a sort of chequer work filling in, in rectangular patches, and a carpet-work pattern over the rest of the visual area.” Herschel wondered whether there might be “a kaleidoscopic power in the sensorium to form regular patterns by the symmetrical combination of casual elements,” a power “working within our own organization [but] distinct from that of our own personality.”

Archway from the Darb-i Imam shrine, Isfahan, Iran. (Credit: K. Dudley and M. Elliff)

Many years later, as a young doctor, I read a little book (really two little books) by the great neurologist Heinrich Klüver, “Mescal” and “Mechanisms of Hallucination.” Klüver not only culled many accounts from the literature, but experimented with mescal himself, and described geometric visual hallucinations typical of the early stages of the mescal experience: “Transparent oriental rugs, but infinitely small … plastic filigreed spherical objets d’art [like] radiolaria … wallpaper designs … cobweb-like figures or concentric circles and squares … architectural forms, buttresses, rosettes, leafwork, fretwork.”

Klüver spoke here of hallucinatory “form constants” and the tendency to “geometrization,” to the “geometrical-ornamental,” seemingly built into the brain-mind. The visions produced by mescal and other hallucinogens would usually progress from these elementary forms of hallucination to elaborate visions of a much more personal and sometimes mystical sort (including scenes of people, animals, and landscapes). But Klüver remarked that the lower-level, geometric hallucinations that preceded these were identical to those found in a variety of conditions: migraine, sensory deprivation, low blood sugar, fever, delirium, or the hypnopompic and hypnagogic states that come immediately before and after sleep. Indeed, even in the absence of any special medical conditions, they could be evoked in anyone by flickering lights, or sometimes even by simply applying pressure to the eyes.

Such geometrical form constants, then, are not dependent on memory or personal experience or desire or imagination. And for those of us with migraine auras — perhaps 10 percent of the population — they are almost like old friends.

Though migraine causes great suffering for millions of people, there has been much success, in the last decade or two, in understanding what goes on during attacks, and how to prevent or minimize them. But we still have only a very primitive understanding of what, to my mind, are among the most intriguing phenomena of migraine — the geometric hallucinations it so often evokes. What we can say, in general terms, is that these hallucinations reflect the minute anatomical organization, the cytoarchitecture, of the primary visual cortex, including its columnar structure — and the ways in which the activity of millions of nerve cells organizes itself to produce complex and ever-changing patterns. We can actually see, through such hallucinations, something of the dynamics of a large population of living nerve cells and, in particular, the role of what mathematicians term deterministic chaos in allowing complex patterns of activity to emerge throughout the visual cortex. This activity operates at a basic cellular level, far beneath the level of personal experience. They are archetypes, in a way, universals of human experience.

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As a child, I was fascinated by patterns, starting with the patterns in our house — the square colored floor tiles we had on the porch, the tessellation of small pentagonal and hexagonal ones in the kitchen; the herringbone pattern on the curtains in my room, and the pattern on my father’s check suit. When I was taken to the synagogue for services, I was more interested in the mosaics of tiny tiles on the floor than in the religious liturgy. And I was fascinated by a pair of antique Chinese cabinets we had in our drawing room, for embossed on their lacquered surfaces were patterns of wonderful intricacy, patterns on different scales, patterns nested within patterns, all surrounded by clusters of tendrils and leaves.

These geometric and scrolling motifs seemed somehow familiar to me, though it did not dawn on my until years later that this was because I had seen them not only in my environment but in my own head, that these patterns resonated with my own inner experience of the intricate tilings and swirls of migraine.

Much later still, when I first saw photographs of the Alhambra, with its intricate geometric mosaics, I started to wonder whether what I had taken to be a personal experience and resonance might in fact be part of a larger whole, whether certain basic forms of geometric art, going back for tens of thousands of years, might also reflect the external expression of universal experiences. Migraine-like patterns, so to speak, are seen not only in Islamic art, but in classical and medieval motifs, in Zapotec architecture, in the bark paintings of Aboriginal artists in Australia, in Acoma pottery, in Swazi basketry — in virtually every culture. There seems to have been, throughout human history, a need to externalize, to make art from, these internal experiences, from the decorative motifs of prehistoric cave paintings to the psychedelic art of the 1960s. Do the arabesques in our own minds, built into our own brain organization, provide us with our first intimations of geometry, of formal beauty?

Whether or not this is the case, there is an increasing feeling among neuroscientists that self-organizing activity in vast populations of visual neurons is a prerequisite of visual perception — that this is how seeing begins. Spontaneous self-organization is not restricted to living systems — one may see it equally in the formation of snow crystals, in the roilings and eddies of turbulent water, in certain oscillating chemical reactions. Here, too, self-organization can produce geometries and patterns in space and time, very similar to what one may see in a migraine aura. In this sense, the geometrical hallucinations of migraine allow us to experience in ourselves not only a universal of neural functioning, but a universal of nature itself.

Information on Dr. Sacks’s book, “Migraine,” can be found here. A complete list of his books can be found here.