I have recently finished reading Hallucinations by Oliver Sacks. A doctor and professor, Oliver Sacks is the author of The Man Who Mistook His Wife for a Hat, Awakenings, Musicophilia, and nine other books. In 1990 Awakenings, which deals with the use of L-Dopa to treat o catatonic patients, was made into a film starring Robert De Niro and Robin Williams. In Hallucinations Sacks is interested in subjective experience and the book is a catalogue of case studies, which is typical of how he presents his work. In the introduction to the book he sets out his stall:
I think of this book … as a sort of natural history or anthology of hallucinations, describing the impact of hallucinations on those who have them, for the power of hallucination is only to be understood from first-person accounts.
Sacks likes to focus on the subjective experience, as opposed to the objective accounts of neurological disease that textbooks prefer. Indeed, Sacks has had his own personal experiences. He has been a lifelong migraine sufferer, whose first attack took place when he was three or four years old:
I was playing in the garden when a shimmering light appeared to my left, dazzlingly bright. It expanded, becoming an enormous arc stretching from the ground to the sky, with sharp, glittering, zigzagging borders and brilliant blue and orange colours. Then behind the brightness came a growing blindness, an emptiness in the 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.
His other experience of hallucinations was with recreational drugs in the 1960s. Sacks used amphetamines, pot and LSD for his neurophenomenological explorations. The results were certainly interesting – he would engage in debates with spiders about whether Bertrand Russell’s paradox had undermined Frege’s system of thought.
Before going any further we need to define our terms. The Merriam Webster defines hallucination thus:
perception of objects with no reality usually arising from disorder of the nervous system or in response to drugs.
The word comes from the Latin alucinatus, the past participle of alucinari – to wander in the mind. It was the French alienist Jean-Étienne Dominique Esquirol who first used hallucinations to refer to any sense disturbance. This is an important point to bear in mind. Hallucinations can occur with any of our senses – and remember we have more than five senses.
Why do we hallucinate? In fact, given how complex perception is, it is hardly surprising that we do. Human perception is imperfect; even a normal brain will fabricate quite a bit of data in order to help us make sense of our complex world. The world we experience around us is a construct that is much more than the raw input of sensation. Often hallucinations are a product of sensory deprivation as the brain does seem to abhor a vacuum. If it doesn’t have anything or enough to process from the outside, it will make something up.
Hallucinations is divided into fifteen chapters, each of which deals with a specific area. Here is a flavour of the book:
In the first chapter, Silent Multitudes: Charles Bonnet Syndrome, we meet Rosalie, a blind woman in her nineties who sees processions of people in brightly coloured “Eastern dress” parade in front of her:
“In drapes, walking up and down stairs … a man who turns towards me and smiles, but he has huge teeth on one side of his mouth. Animals, too. I see this scene with a white building, and it is snowing—a soft snow, it is swirling. I see this horse (not a pretty horse, a drudgery horse) with a harness, dragging snow away … but it keeps switching.… I see a lot of children; they’re walking up and down stairs. They wear bright colours—rose, blue—like Eastern dress.” Curiously, Rosalie’ eyes were open and even though she could see nothing, her eyes moved here and there, as if looking at an actual scene. Sacks found nothing suggestive of confusion or delusion. Neurologically, she was completely normal. He reassured her that she was not going crazy. Hallucinations are not uncommon in those with blindness or impaired sight, and that these visions are not “psychiatric” but a reaction of the brain to the loss of eyesight. She was suffering from Charles Bonnet syndrome, a condition that causes patients with significant visual loss to have complex visual hallucinations.
In the second chapter, The Prisoner’s Cinema: Sensory Deprivation, introduces us to the noted sceptic Michael Shermer, who spends his life debunking the paranormal. He used to take part in cycling races. In the early hours of the morning of August 8, 1983, he was travelling along a lonely rural highway in Nebraska as part of the transcontinental Race Across America. He had not been riding for 83 straight hours and had covered 1,259 miles. This is what he experienced:
“A large craft with bright lights overtook me and forced me to the side of the road. Alien beings exited the craft and abducted me for 90 minutes, after which time I found myself back on the road with no memory of what transpired inside the ship.…” After taking a nap, Shermer realized that he had been hallucinating, but at the time it had seemed completely real.
In chapter three, A Few Nanograms of Wine: Hallucinatory Smells, we hear about Mary B., a Canadian woman, with dysosmia, the impairment of olfactory stimuli processing which leads to an altered sense of smell. After a hysterectomy performed under general anaesthesia, she felt physically fine, soon returning to her Pilates and ballet classes. But she would be locked in an invisible prison by a disorder no one could see. Tomatoes and oranges started tasting metallic and a bit rotten, and cottage cheese tasted like sour milk. Then lettuce began to smell and taste of turpentine, and spinach, apples, carrots and cauliflower tasted slightly rotten. Fish and meat, especially chicken, smelt as if they’d been rotting for a week. Bread tasted rancid; chocolate, like machine oil. The only meat or fish she could eat was smoked salmon, which she started having three times a week. It was gradually getting worse and worse. Wine smelt revolting; so did anybody who was wearing scent. Her husband had to have coffee at work so disgusting was the smell to her. She tried in vain to find a pattern:
“There was no rhyme or reason to it,” she wrote. “How could lemons taste okay but not oranges; garlic, but not onions?”
In the chapter on epilepsy, The “Sacred” Disease, Sacks refers to an epileptic woman who believed that she was receiving messages from God telling her to run for Congress. This message proved popular with many voters. Although she lacked political skills or experience and was standing as a Republican in what was a safe Democratic district, she only lost by a narrow margin.
In chapter ten, Delirious, Sacks tells us about the poet Richard Howard’s delirium following back surgery. The day after the operation, lying in his hospital bed and looking up, he saw small animals all around the edges of the ceiling. They were the size of mice but had heads like those of deer. They felt so real that Howard could not see them. The following day, he began seeing a “pageant of literature.” The doctors, nurses, and ancillary staff were all dressed up as nineteenth-century, literary figures. The pageant was taking place on several floors of the hospital simultaneously. As the floors seemed transparent to him, he could watch all the levels of the performance at once. When real visitors came, the pageant would disappear, but as soon as they left, it would start again Sacks says that Richard is a man with an acute and critical mind, but hallucinations can be so powerful that all this goes out of the window.
In the twelfth chapter, Narcolepsy and Night Hags, we meet Stephanie W. whose first narcoleptic hallucination occurred when she was on her way home from kindergarten at the age of five. They continued into adulthood. While some were benign, such as an angel appearing over a highway exit, others were terrifying like seeing the people before her take on the appearance of being dead. Now that she has been correctly diagnosed and is taking effective medication, her life has been transformed.
In chapter 14, Doppelgängers: Hallucinating Oneself, Sacks deals with patients who see doppelgangers of themselves. A particularly weird form is the heautoscopy, in which where there is interaction between the person and his double, more often than not hostile. There may even be confusion as to who is the “original” and who the “double”. Sacks cites a 1994 paper describing an episode in a young man with temporal lobe epilepsy. The patient had woken up with a dizzy feeling. He got up, but he saw himself still lying in bed. This made him angry with the guy in bed, even though he knew it was himself. In an attempt to wake the body in the bed, he first shouted at it; then tried to shake it before finally jumping on his alter ego in the bed. The lying body did not react. It was then that the patient began to feel bewildered about his double existence. He became scared because he could no longer tell which of the two he really was. He just wanted to become one person again and. He decided to jump out of the window of his third-floor flat “in order to stop the unbearable feeling of being divided in two.” He hoped that this would frighten the double in bed into merging with him again. The next thing he remembered was waking up in pain in the hospital.
Hallucinations is an excellent introduction to this subject. I would have liked a chapter on schizophrenic hallucinations, but Sacks felt that that would have required another book to do it justice. This is a very humane book, which seeks to lessen the stigma of hallucinations – most people associate hallucinations with mental illness. Here is Sacks describing his own methodology:
I feel that if I describe things respectfully, tenderly, and truly, then this is an important thing to do. It’s not voyeurism, it’s not exploitation, but an essential form of knowledge. I think the detailed case history has no equal in conveying understanding, not only of what a condition is like, but of the ways in which a person may respond to a condition
In his work with elderly patients Sacks has found that quite a lot of older people of sound mind, but with poor vision or hearing, will start getting hallucinations. Many are afraid to mention this because, as well as the social stigma, they think it may be a sign of dementia or madness. Sacks want to say that this is not necessarily so. People who experience them are often capable of leading completely normal lives.