By Oliver Sacks
Knopf, 320 pages, $30
HALLUCINATE anything interesting lately? In a compelling book arguing for the importance of hallucinations to human experience, British neurologist and author Oliver Sacks examines an assortment of hallucinatory experiences, many of them his own.
While some of the hallucinations he describes are terrifying, some are very beautiful and some can be described as, at best, humdrum. Compiled and analyzed by Sacks, they reveal a great deal about the functioning of the human brain and about the role of misperception in shaping cultural practices and spiritual beliefs.
Sacks, a New York-based professor of neurology and psychiatry, is well known for his work as a prolific popularizer of neuroscience. Now in his early 80s, he is the author of 10 books, most notably The Man Who Mistook His Wife for a Hat (1985) and Awakenings (1973), which was adapted into movie starring Robin Williams.
As with other books by Sacks, Hallucinations draws on decades of clinical experience. While Sacks shares his knowledge of individual cases and of recent developments in the field of neuroscience, he also makes excellent use of 19th-century scientific writing.
Interested in the work of earlier generations, of the pioneers of neurological research, he quotes extensively from Victorian commentators and in doing so shares some compelling insights as well as some wonderfully poetic scientific writing.
Sacks' most interesting source is, however, his extensive personal experience with hallucination, the product of weekends devoted to self-experimentation while a resident in UCLA's neurology department in the early 1960s. Drawing on memories of time spent under the influence of what he refers to as "a pharmacologic launch pad," Sacks describes making breakfast for visiting friends only to discover that he had hallucinated their presence.
He also recalls a conversation on "rather technical matters of analytical philosophy" that he had with a friendly and surprisingly well-informed spider.
While memories of misspent weekends can be entertaining, Sacks' candid account of his lonely 32nd birthday is painful. He describes how, to celebrate the occasion, he broke into the drug cabinet of his parents, who were physicians, and injected a large amount of morphine.
The result was a 12-hour stupor that Sacks spent staring at an elaborate hallucination of the battle of Agincourt, unfolding on the sleeve of his dressing gown.
While drug use is a major theme of the book, Sacks gives equal attention to two other causes of hallucination: disease and deprivation. In chapters on conditions such as narcolepsy, Parkinson's disease and epilepsy, Sacks explores the role of disease in the brain's creation and projection of unreal images. He chooses, however, to leave schizophrenia largely untouched, suggesting that it is too complex for the limited treatment he could give it in a book of this kind.
In chapters on deprivation, Sacks explores how even short periods of sensory deprivation can prompt complex hallucinations. In a particularly engaging chapter on Charles Bonnet Syndrome, Sacks describes cases in which vision loss triggers elaborate visual hallucinations in people living with visual disabilities.
While the book is, like Sacks' others, aimed at a general audience, readers might find themselves working hard to keep up with a quick moving conversation that does not shy away from the use of sometimes challenging technical terminology.
They are likely to find the insights of the book a fair compensation for the extra effort. This book does more than detail the causes and the nature of hallucinations. It also grapples with our fascination with hallucination, our debt to it and our desire for it.
Vanessa Warne is a University of Manitoba English professor.