Hallucinations

by Oliver Sacks

  Perhaps such experiences are at the root of our human obsession with pattern and the fact that geometrical patterns find their way into our decorative arts. As a child, I was fascinated by the patterns in our house—the square colored floor tiles on the front porch, the small hexagonal ones in the kitchen, the herringbone pattern on the curtains in my room, the check pattern on my father’s 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 loved the pair of antique Chinese cabinets in our drawing room, for embossed on their lacquered surfaces were designs of wonderful intricacy 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 me until years later that this was because I had seen them in my own head, that these patterns resonated with my own inner experience of the intricate tilings and swirls of migraine.

  Migraine-like patterns, indeed, can be found in Islamic art, 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, going back tens of thousands of years. There seems to have been, throughout human history, a need to externalize and make art from these internal experiences, from the cross-hatchings of prehistoric cave paintings to the swirling psychedelic art of the 1960s. Do the arabesques and hexagons in our own minds, built into our brain organization, provide us with our first intimations of formal beauty?

  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 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.

  1. A migraine headache often occurs on only one side (hence the term, which derives from the Greek for “hemi” and “cranium”). But it can also be on both sides, and can range from a dull or throbbing ache to excruciating pain, as J. C. Peters described in his 1853 A Treatise on Headache:

  The character of the pains varied very much; most frequently they were of a hammering, throbbing or pushing nature.… [in other cases] pressing and dull … boring with sense of bursting … pricking … rending … stretching … piercing … and radiating.… In a few cases it felt as if a wedge was pressed into the head, or like an ulcer, or as if the brain was torn, or pressed outwards.

  2. This woman, Ingrid K., also reported that she sometimes has “another strange experience just before the migraine … I think I recognize everyone I see. I don’t know who they are … but everyone looks familiar.” Other correspondents have described a similar “hyperfamiliarity” at the start of migraine—and this feeling is occasionally part of an epileptic aura, as Orrin Devinsky and his colleagues have described.

  8

  The “Sacred” Disease

  Epilepsy affects a substantial minority of the population, occurs in all cultures, and has been recognized since the dawn of recorded history. It was known to Hippocrates as the sacred disease, a disorder of divine inspiration.1 And yet in its major, convulsive form (the only form recognized until the nineteenth century), it has attracted fear, hostility, and cruel discrimination. It still carries a good deal of stigma today.

  Epileptic attacks—often called seizures or fits—can take a dozen or more forms. These have in common a sudden onset (sometimes without any warning, but sometimes with a characteristic prodrome or aura) and a basis in a sudden, abnormal electrical discharge in the brain. In generalized seizures, this discharge arises from both halves of the brain simultaneously. In a grand mal seizure, there is violent, convulsive movement of the muscles, biting of the tongue, and sometimes foaming at the mouth; there may also be a harsh, inhuman-sounding “epileptic cry.” Within seconds, the person having a grand mal seizure will lose consciousness and fall to the ground (epilepsy was also called “the falling sickness”). Such attacks can be terrifying to see.

  In a petit mal seizure, there is only a transient loss of consciousness—the person seems to be “absent” for a few seconds, but may then continue a conversation or a chess game without realizing, or anyone else realizing, that anything unusual has happened.

  In contrast to such generalized seizures, which arise from an inborn, genetic sensitivity of the brain, partial seizures arise from a particular area of damage or sensitivity in one part of the brain, an epileptic focus, which may be congenital or the result of an injury. The symptoms of partial seizures depend on the location of the focus: they may be motor (twitching of certain muscles), autonomic (nausea, a rising feeling in the stomach, etc.), sensory (abnormalities or hallucinations of sight, sound, smell, or other sensations), or psychic (sudden feelings of joy or fear without apparent cause, déjà vu or jamais vu, or sudden, often unusual, trains of thought). Partial seizure activity may be confined to the epileptic focus, or it may spread to other areas of the brain, and occasionally it leads to a generalized convulsion.

  Partial or focal seizures were only recognized in the second half of the nineteenth century—a time when focal deficits of all kinds (for instance, aphasia, the loss of linguistic ability, or agnosia, the loss of ability to identify objects) were being described and attributed to damage in specific areas of the brain. This correlation of cerebral pathology with specific deficits, or “negative” symptoms, led to the understanding that there are many different centers in the brain crucial to certain functions.

  But Hughlings Jackson (sometimes called the father of English neurology) paid equal attention to the “positive” symptoms of neurological disease—symptoms of overactivity, such as seizures, hallucinations, and deliria. He was a minute and patient observer, and he was the first to recognize “reminiscence” and “dreamy states” in complex seizures. We still speak of focal motor seizures which start in the hands and “march” up the arm as Jacksonian epilepsy.

  Jackson was also an extraordinary theorist, who proposed that higher and higher levels had evolved in the human nervous system—and that these were hierarchically organized, with higher centers constraining lower ones. Thus, he thought, damage in the higher centers might cause “release” activity in the lower ones. For Jackson, epilepsy was a window into the organization and workings of the nervous system (as migraine was for me). “He who is faithfully analyzing many different cases of epilepsy,” Jackson wrote, “is doing far more than studying epilepsy.”

  Jackson’s younger partner in the enterprise of describing and classifying seizures was William Gowers, and where Jackson’s writing was complex, convoluted, and full of reservations, Gowers’s was simple, transparent, and lucid. (Jackson never wrote a book, but Gowers wrote many, including his 1881 Epilepsy and Other Chronic Convulsive Diseases.)2

  Gowers was especially drawn to the visual symptoms of epilepsy (he had previously written a book on ophthalmology), and he enjoyed describing simple visual seizures, as with one patient, for whom, he wrote:

  The warning was always a blue star, which appeared to be opposite the left eye, and to come nearer until consciousness was lost. Another patient always saw an object, not described as light, before the left eye, whirling round and round. It seemed to come nearer and nearer, describing larger circles as it approached, until consciousness was lost.

  Jen W., an articulate young woman, came to see me several years ago. She told me that when she was four, she saw “a ball of colored lights on the right side, spinning, very defined.” The ball of colored lights spun for a few seconds and was succeeded by a greyish cloud to the right,
obscuring her vision to that side for two or three minutes.

  She had further visions of the spinning ball, always in the same place, four or five times a year, but she assumed that this was normal, something everyone saw. When she was six or seven, the attacks took on a new aspect: the colored ball was followed by a headache on one side of her head, often accompanied by an intolerance of light and sound. She was taken to a neurologist, but an EEG and CAT scan revealed nothing, and Jen was diagnosed with migraine.

  When she was thirteen or so, the attacks became longer, more frequent, and more complicated. Sometimes these frightening attacks led to complete blindness for several minutes, along with an inability to understand what people were saying. When she tried to talk, she could only utter gibberish. At this point, she was diagnosed with “complicated migraine.”

  When she was fifteen, Jen had a grand mal seizure—she had a convulsion and fell to the floor, unconscious. She had many EEGs and an MRI, all of which were interpreted as normal, but finally a detailed investigation by an epilepsy specialist revealed a clear epileptic focus in the left occipital lobe and an area of abnormal cortical architecture in the same area. She was put on antiepileptic drugs, and these prevented further convulsions but did little to help with her purely visual seizures, which became increasingly frequent, sometimes occurring many times a day. She said they could be precipitated by “bright sunlight, flickering shadows, or brightly colored scenes with movement and fluorescent lights.” This extreme sensitivity to light drove her to a very restricted life, an effectively nocturnal and crepuscular existence.

  Since her visual seizures did not respond to medication, a surgical approach was suggested, and when Jen was twenty, she had the abnormal area in her left occipital lobe removed. Before the surgery, while the occipitotemporal cortex was being mapped by electrical stimulation, she saw “Tinkerbell” and “cartoon figures.” This was the only time she has ever had complex visual hallucinations; her visual seizures are normally of a simple sort, with the spinning ball to the right or, occasionally, a shower of “sparklers” in this area.

  The immediate effect of the surgery was very good. She was thrilled that she no longer had to stay inside, and she went back to teaching gymnastics. She found that a very small dose of antiepileptic medication could now control most of her visual seizures, although she remained sensitive to stress, missing meals, not getting enough sleep, and flickering or fluorescent lights. Her surgery left her with blindness in the lower right quadrant of her visual field, and although she can navigate pretty well in the world with this blind spot, she avoids driving. Her symptoms returned, though less severely, a few years after the surgery. She says, “Epilepsy is a major challenge in my life, but I’ve developed strategies to manage it.” She is working now on a PhD in biomedical engineering (with a focus on neuroscience), not least because of the intricate ways in which a neurological disorder has affected her own life.

  When the epileptic focus lies at higher levels of the sensory cortex, in the parietal or the temporal lobes, the epileptic hallucinations may be much more complex. Valerie L., a gifted twenty-eight-year-old doctor, had what were called “migraines” from an early age—one-sided headaches preceded by twinkling blue dots. But when she was fifteen, she had a new, unprecedented experience. She said, “I had run a ten-mile race the day before … the next day I felt very strange.… I had a six-hour nap after a full night of sleep, which was most atypical for me, and then I went to temple with my family: it was a long service, a lot of standing.” She started to see halos around objects and said to her sister, “Something weird is happening.” And then a glass of water at which she was looking suddenly “multiplied itself,” so that she saw glasses of water wherever she looked, dozens of them, covering the walls and the ceiling. This went on for perhaps five seconds, “the longest five seconds of my life,” she said.

  Then she lost consciousness. She came to in an ambulance, hearing the driver say, “I have a fifteen-year-old girl with a seizure,” and then realized with a start that she was the girl.

  When she was sixteen, she had a second, similar attack and was put on antiepileptic medication for the first time.

  A third grand mal seizure occurred a year later. Valerie saw vague black shapes in the air (“like Rorschach ink blots”), and as she continued to look, these transformed themselves into faces—her mother’s face and the faces of other relatives. The faces were motionless, flat, two-dimensional, and “like negatives,” so that light-skinned faces were seen as dark, and vice versa. They had wavering edges, “as if enveloped in flame,” in the thirty seconds before she had a convulsion and lost consciousness. After this, her doctors changed her antiepileptic medication, and she has had no more grand mal seizures since, though she continues to get visual auras or visual seizures, on average twice a month, more if she is stressed or sleep-deprived.

  On one occasion, when Valerie was in college, she felt weak and not quite herself, so she went to her parents’ house for the evening. She and her mother were sitting and talking as Valerie lay in bed, when she suddenly “saw” e-mails she had received earlier in the day plastered all over her bedroom. One particular e-mail was multiplied, and one of its images was superimposed on her mother’s face, although she could see the face through it. The image of the e-mail was so clear and exact that she could read every word. Objects from her dorm room appeared everywhere she looked. It was a particular object, whether perceived or remembered, that got multiplied, never a whole scene. Her visual multiplications and reiterations are now of familiar faces for the most part, “projected” onto the walls, the ceiling, any available surface. This sort of spreading of visual perceptions in space (polyopia) and in time (palinopsia) was vividly described by Macdonald Critchley, who first used the term palinopsia (he originally called it paliopsia).

  Valerie may also experience perceptual changes in relation to her seizures; indeed, her first intimation of a seizure is sometimes that her own reflection looks different—her eyes, in particular. She may feel, “This is not me,” or “It’s a close relative.” If she can go to sleep, she can avert a seizure. But if she has not been able to sleep well, other people’s faces may also look different the next morning—“strange” and distorted, especially around the eyes, though not so much that they are unrecognizable. Between attacks, she may have the opposite feeling—a hyperfamiliarity, so that everyone seems familiar to her. It is a feeling so overwhelming that sometimes she cannot resist greeting a stranger, even though, intellectually, she can say to herself, “This is just an illusion. It seems most unlikely that I have ever met this person.”

  Despite her epileptic auras, Valerie lives a full and productive life, keeping up with a demanding career. She is reassured by three things: that she has not had a generalized seizure for ten years, that whatever is provoking her attacks is not progressive (she had a minor head injury when she was twelve and probably has a small temporal lobe scar from that injury), and that medication can provide adequate control.

  Both Jen and Valerie were initially misdiagnosed as having “migraine”—such confusion of epilepsy and migraine is not uncommon. Gowers was at pains to differentiate them in his 1907 book, The Border-land of Epilepsy, and his lucid descriptions bring out some of the differences between the two ailments as well as some of the similarities. Both migraine and epilepsy are paroxysmal—they present themselves suddenly, go through their course, and then disappear. Both show a slow movement or “march” of symptoms and the electrical disturbance underlying them—in migraine this takes fifteen or twenty minutes; in epilepsy it is often just a matter of seconds. It is unusual for people with migraine to have complex hallucinations, whereas epilepsy commonly affects higher parts of the brain; there it may evoke very complex, multisensorial “reminiscences” or dreamlike fantasies, like one of Gowers’s patients, who saw “London in ruins, herself the sole spectator of this desolate scene.”

  Laura M., a psychology major in college, at first ignored her “strange
attacks” but finally consulted an epilepsy specialist, who found that she was “experiencing stereotypic episodes of déjà vu, visual and emotional flashbacks of a dream or series of dreams, usually one of five dreams … which she had in the past ten years.” These could happen several times daily and were aggravated by tiredness or by marijuana. When she started taking an antiepileptic medication, her attacks decreased in severity and frequency, but she had increasingly unacceptable side effects—in particular, a feeling of overstimulation followed by a “crash” later in the day. She took herself off the medication and reduced her use of marijuana, and now her attacks are at a tolerable level, perhaps half a dozen per month. They last only a few seconds, and although the internal feeling is overwhelming and she may “zone out” a little, others might not notice anything amiss. The only physical symptom she feels during these attacks is an impulse to roll her eyeballs back, which she resists when others are around.

  When I met Laura, she said she had always had vivid, richly colored dreams that she could easily remember, and she characterized most of them as “geographic,” involving complex landscapes. She felt that the visual hallucinations or flashbacks she had in her seizures all drew on the landscapes of those dreams.