Hallucinations

by Oliver Sacks

  Tony Cicoria, a surgeon, was struck by lightning a few years ago and suffered a cardiac arrest. (I tell his whole, complex story in Musicophilia.) He recounted this to me:

  I remember a flash of light … hit me in the face. Next thing I remember, I was flying backwards … [then] I was flying forwards. I saw my own body on the ground. I said to myself, “Oh shit, I’m dead.” I saw people converging on the body. I saw a woman … position herself over my body, give it CPR.

  Cicoria’s OBE became more complex. “There was a bluish-white light … an enormous feeling of well-being and grace”; he felt he was being drawn into heaven (his OBE had evolved into a “near-death experience,” which is not the case with most OBEs), and then—it could have been little more than thirty or forty seconds from the moment he was struck by lightning—“Slam! I was back.”

  The term “near-death experience” (NDE) was introduced by Raymond Moody in his 1975 book Life After Life. Moody, culling information from many interviewees, delineated a remarkably uniform and stereotyped set of experiences common to many NDEs. A majority of people felt that they were being drawn into a dark tunnel and then propelled towards a brightness (which some interviewees called “a being of light”); and, finally, they sensed a limit or barrier ahead—most interpreted this as the boundary between life and death. Some experienced a rapid replay or review of events in their lives; others saw friends and relatives. In a typical NDE, all this was suffused with a sense of peace and joy so intense that being “forced back” (into one’s body, into life) might be accompanied by a strong sense of regret. Such experiences were felt as real—“more real than real,” as was often commented. Many of Moody’s interviewees favored a supernatural interpretation for these remarkable experiences, but others have increasingly tended to regard them as hallucinations, albeit of an extraordinarily complex kind. A number of researchers have sought a natural explanation in terms of brain activity and blood flow, since NDEs are especially associated with cardiac arrest and may also occur in faints, when blood pressure plunges, the face becomes ashen, and the head and brain are drained of blood.

  Kevin Nelson and his colleagues at the University of Kentucky have presented evidence suggesting that, with the compromise of cerebral blood flow, there is a dissociation of consciousness so that, although awake, the subjects are paralyzed and subject to the dreamlike hallucinations characteristic of REM sleep (“REM intrusions”)—in a state, therefore, with resemblances to sleep paralysis (NDEs are also commoner in people prone to sleep paralysis). Added to this are various special features: the “dark tunnel” is correlated, Nelson feels, with the compromise of blood flow to the retinas (this is well known to produce a constriction of the visual fields, or tunnel vision, and may occur in pilots subjected to high g-stresses). The “bright light” Nelson correlates with a flow of neuronal excitement moving from a part of the brain stem (the pons) to subcortical visual relay stations and then to the occipital cortex. Added to all these neurophysiological changes may be a sense of terror and awe going with the knowledge that one is undergoing a mortal crisis—some subjects have actually heard themselves pronounced dead—and the wish that dying, if imminent and inevitable, should be peaceful and perhaps a passage to a life after death.

  Both Olaf Blanke and Peter Brugger have studied such phenomena in several patients with severe epilepsy. Like Wilder Penfield’s patients in the 1950s, people with intractable seizures that do not respond to medication may need surgery to remove the epileptic focus responsible. Such surgery requires extensive testing and mapping to find the seizure focus and to avoid damaging vital areas. The patient must be awake during this procedure, so that he can report what he is experiencing. Blanke was able to demonstrate that stimulating certain areas of the brain’s right angular gyrus invariably caused OBEs in one such patient, as well as feelings of lightness and levitation and changes in body image; the patient saw her legs “becoming shorter” and moving towards her face. Blanke et al. speculate that the angular gyrus is a crucial node in a circuit that mediates body image and vestibular sensations, and that “the experience of dissociation of self from the body is a result of failure to integrate information from the body with vestibular information.”

  At other times, one is not disembodied but sees a double of oneself from one’s normal viewpoint, and the other self often mimics (or shares) one’s own postures and movements. These autoscopic hallucinations are purely visual and usually fairly brief—they may occur, for instance, in the few minutes of a migraine or epileptic aura. In his delightful history of migraine, “Migraine: From Cappadocia to Queen Square,” Macdonald Critchley describes this in the great naturalist Carl Linnaeus:

  Often Linnaeus saw “his other self” strolling in the garden parallel with himself, and the phantom would mimic his movements, i.e. stoop to examine a plant or to pick a flower. Sometimes the alter ego would occupy his own seat at his library desk. Once at a demonstration to his students he wanted to fetch a specimen from his room. He opened the door rapidly, intending to enter, but pulled up at once saying, “Oh! I’m there already.”

  A similar hallucination of a double was seen regularly by Charles Lullin, the grandfather of Charles Bonnet, for about three months, as Douwe Draaisma describes:

  One morning as he was quietly smoking his pipe at the window, he saw on his left a man leaning casually against the window frame. Except for the fact that he was a head taller, the man looked exactly like him: he was also smoking a pipe, and he was wearing the same cap and the same dressing gown. The man was there again the next morning, and he gradually became a familiar apparition.

  The autoscopic double is literally a mirror image of oneself, with right transposed to left and vice versa, mirroring one’s positions and actions. The double is a purely visual phenomenon, with no identity or intentionality of its own. It has no desires and takes no initiatives; it is passive and neutral.3

  Jean Lhermitte, reviewing the subject of autoscopy in 1951, wrote: “The phenomenon of the double can be produced by many other diseases of the brain besides epilepsy. It appears in general paralysis [neurosyphilis], in encephalitis, in encephalosis of schizophrenia, in focal lesions of the brain, in post-traumatic disorders.… The apparition of the double should make one seriously suspect the incidence of a disease.”

  It is now thought that a substantial number—perhaps a third—of all cases of autoscopy may be associated with schizophrenia, and even cases of manifestly physical or organic origin may be sensitive to suggestion. T. R. Dening and German Berrios described a thirty-five-year-old man whose apparitions were related to temporal lobe seizures following a head injury. The man said that he had once seen his ties hanging up as a rack of snakes, but when asked whether he had any outright hallucinations or autoscopic experiences, he said no. A week later, he came in for another appointment in a state of some excitement, for he had now had an autoscopic experience:

  He had been sitting in a café, when he was suddenly aware of an image of himself, about 15–20 yards away, looking in through the café window. The image was dark and looked like him at the age of nineteen (when his accident occurred). It did not speak and probably lasted for less than a minute. He felt amazed and uncomfortable, as though physically struck, and he felt he had to get up and leave. It is difficult not to suppose that the timing of this episode was influenced by the questions asked by the psychiatrist in the previous week.

  While most examples of autoscopy are fairly brief, long-lasting autoscopy has also been recorded. Zamboni et al. provide a detailed description of this in a 2005 paper. Their patient, B.F., was a young woman who developed eclampsia in pregnancy and was comatose for two days. As she started to recover, it was evident that she was cortically blind and had a partial paralysis on both sides as well as an unawareness of her left side and of the left side of space, a hemi-neglect. With further recovery, her visual fields became full and she could discriminate color, but she was profoundly agnosic, unable to recognize objects or even shapes.
At this stage, Zamboni et al. wrote, their patient first started seeing her own image as if reflected in a mirror, about a meter in front of her. The image was transparent, as though it were set “in a sheet of glass,” but a bit blurry. It was life-sized and consisted of a head and shoulders, though if she looked down, she could see its legs, too. It was always dressed exactly like her. It disappeared when she closed her eyes and reappeared the moment she opened them (although, as the novelty wore off, she was able to “forget” the image for hours at a time). She had no special feelings for the image and never attributed any thoughts or feelings or intentionality to it.

  As B.F.’s agnosia disappeared, the mirror image gradually faded, and it had vanished entirely by six months after the original brain injury. Zamboni et al. suggested that the unusual persistence of this mirror image may have been associated with her severe visual loss, along with disturbances of multisensory integration (visual, tactile, proprioceptive, etc.) at higher levels, perhaps in the parietotemporal junction.

  An even stranger and more complex form of hallucinating oneself occurs in “heautoscopy,” an extremely rare form of autoscopy where there is interaction between the person and his double; the interaction is occasionally amiable but more often hostile. Moreover, there may be deep bewilderment as to who is the “original” and who the “double,” for consciousness and sense of self tend to shift from one to the other. One may see the world first with one’s own eyes, then through the double’s eyes, and this can provoke the thought that he—the other—is the real person. The double is not construed as passively mirroring one’s posture and actions, as with autoscopy; the heautoscopic double can do, within limits, whatever it wants to (or it may lie still, doing nothing at all).

  “Ordinary” autoscopy—such as Linnaeus and Lullin experienced—seems relatively benign; the hallucination is purely visual, a mirroring which appears only occasionally, has no pretensions to autonomy, no intentionality, and attempts no interactions. But the heautoscopic double, mocking or stealing one’s identity, may arouse feelings of fear and horror and provoke impulsive and desperate acts. In a 1994 paper, Brugger and his colleagues described such an episode in a young man with temporal lobe epilepsy:

  The heautoscopic episode occurred shortly before admission. The patient stopped his phenytoin medication, drank several glasses of beer, stayed in bed the whole of the next day, and in the evening he was found mumbling and confused below an almost completely destroyed large bush just under the window of his room on the third floor.… The patient gave the following account of the episode: on the respective morning he got up with a dizzy feeling. Turning around, he saw himself still lying in bed. He became angry about “this guy who I knew was myself and who would not get up and thus risked being late at work.” He tried to wake the body in the bed first by shouting at it; then by trying to shake it and then repeatedly jumping on his alter ego in the bed. The lying body showed no reaction. Only then did the patient begin to be puzzled about his double existence and become more and more scared by the fact that he could no longer tell which of the two he really was. Several times his bodily awareness switched from the one standing upright to the one still lying in bed; when in lying in bed mode he felt quite awake but completely paralysed and scared by the figure of himself bending over and beating him. His only intention was to become one person again and, looking out of the window (from where he could still see his body lying in bed), he suddenly decided to jump out “in order to stop the intolerable feeling of being divided in two.” At the same time, he hoped that “this really desperate action would frighten the one in bed and thus urge him to merge with me again.” The next thing he remembers is waking up in pain in the hospital.

  The term “heautoscopy” (sometimes spelled héautoscopy), introduced in 1935, is not always regarded as a useful one. T. R. Dening and German Berrios, for example, write, “We see no advantage in this term; it is pedantic, almost unpronounceable, and not widely used in ordinary practice.” They see not a dichotomy but a continuum or spectrum of autoscopic phenomena, in which the sense of relationship to one’s autoscopic image may vary from minimal to intense, from indifferent to impassioned, and the sense of its “reality” may be equally variable and inconsistent. In a 1955 paper, Kenneth Dewhurst and John Pearson described a schoolteacher who, at the start of a subarachnoid hemorrhage, saw an autoscopic “double” for four days:

  It appeared quite solid as if seen in a mirror, dressed exactly as he was. It accompanied him everywhere; at meal-times it stood behind his chair and did not reappear till he had finished eating. At night it would undress and lie down on the table or couch in the next room of his flat. The double never said anything to him or made any sign, but only repeated his actions: it had a constant sad expression. It was obvious to the patient that this was all a hallucination, but nevertheless it had become sufficiently a part of himself for the patient to draw a chair up for his double when he first visited his private doctor.

  In 1844, a century before the term was coined, A. L. Wigan, a physician, described an extreme case of heautoscopy with tragic consequences:

  I knew a very intelligent and amiable man, who had the power of thus placing before his eyes himself, and often laughed heartily at his double, who always seemed to laugh in turn. This was long a subject of amusement and joke, but the ultimate result was lamentable. He became gradually convinced that he was haunted by [his other] self. This other self would argue with him pertinaciously, and to his great mortification sometimes refute him, which, as he was very proud of his logical powers, humiliated him exceedingly. He was eccentric, but was never placed in confinement or subjected to the slightest restraint. At length, worn out by the annoyance, he deliberately resolved not to enter on another year of existence—paid all his debts—wrapped up in separate papers the amount of the weekly demands—waited, pistol in hand, the night of the 31st of December, and as the clock struck twelve fired it into his mouth.

  The theme of the double, the doppelgänger, a being who is partly one, partly Other, is irresistible to the literary mind, and is usually portrayed as a sinister portent of death or calamity. Sometimes, as in Edgar Allan Poe’s “William Wilson,” the double is the visible and tangible projection of a guilty conscience that grows more and more intolerable until, finally, the victim turns murderously on his double and finds that he has stabbed himself. Sometimes the double is invisible and intangible, as in Guy de Maupassant’s story “Le Horla,” but this double nonetheless leaves evidence of his existence (for instance, he drinks the water that the narrator sets out in his night bottle).

  At the time he wrote this, de Maupassant often saw a double himself, an autoscopic image. As he remarked to a friend, “Almost every time when I return home I see my double. I open the door and see myself sitting in the armchair. I know it’s a hallucination the moment I see it. But isn’t it remarkable? If you had not a cool head, wouldn’t you be afraid?”

  De Maupassant had neurosyphilis at this point, and when the disease grew more advanced, he became unable to recognize himself in a mirror and, it is reported, would greet his image in a mirror, bow, and try to shake hands with it.

  The persecuting yet invisible Horla, while perhaps inspired by such autoscopic experiences, is a different thing altogether; it belongs, like William Wilson and Golyadkin’s double in Dostoevsky’s novella, to the essentially literary, Gothic genre of the doppelgänger, a genre which had its heyday from the late eighteenth century to the turn of the twentieth.

  In real life—despite the extreme cases reported by Brugger and others—heautoscopic doubles may be less malign; they may even be good-natured or constructive moral figures. One of Orrin Devinsky’s patients, who had heautoscopy in association with his temporal lobe seizures, described this episode: “It was like a dream, but I was awake. Suddenly, I saw myself about five feet in front of me. My double was mowing the lawn, which is what I should have been doing.” This man subsequently had more than a dozen such episodes just before seizur
es, and many others that were apparently unrelated to seizure activity. In a 1989 paper, Devinsky et al. wrote:

  His double is always a transparent, full figure that is slightly smaller than life size. It often wears different clothing than the patient and does not share the patient’s thoughts or emotions. The double is usually engaged in an activity that the patient feels he should be doing, and he says, “that guy is my guilty conscience.”

  Embodiment seems to be the surest thing in the world, the one irrefutable fact. We think of ourselves as being in our bodies, and of our bodies as belonging to us, and us alone: thus we look out on the world with our own eyes, walk with our own legs, shake hands with our own hands. We have a sense, too, that consciousness is in our own head. It has long been assumed that the body image or body schema is a fixed and stable part of one’s awareness, perhaps in part hardwired, and largely sustained and affirmed by the continuing proprioceptive feedback from joint and muscle receptors regarding the position and movement of one’s limbs.