Mia Lipman: In Hallucinations, you mention that your childhood migraines are one of the reasons you became a neurologist. How did they help shape your path?
Dr. Sacks: My experiences go back to my first memories of when I was three or four, suddenly seeing a brilliant zigzag which seemed to be vibrating, then enlarged and covered everything to one side. This has happened innumerable times since, but that first time was very terrifying…I know I was in the garden, and part of the garden wall seemed to disappear, and I asked my mother about it. She too had classical migraines, so she explained what it was about and said that it was benign and it would only last a few minutes, and I'd be none the worse. So though I'm not in love with the attacks, it's nice to know that one can live with this quite well.
So that early experience made you curious about why this was happening to you?
Indeed, and there were other experiences. Sometimes it was just color, perhaps in one half of the visual field, or things would be frozen and I couldn't see any movement. So I think this gave me a very early feeling that it's only the privilege of a normal brain which allows us to see the way we do—and that what seems to be a simple vision in fact must have dozens of different components, and any one of these can go down. So it was a learning experience for me as well.
Ah, I thought that would come up. [Laughing.]
Of course, it's the best part! I especially liked your description of the results as "a mix of the neurological and the divine." What did this self-experimentation teach you about your field, as well as personally?
I can't conceal that my motives were sort of mixed, but these were learning experiences as well as recreational ones, and occasionally terrifying ones. The gain, I think, [is that] it's a way of revealing various capacities and incapacities in the brain, including, perhaps, mystical ones…I quote William James, who, after taking nitrous oxide, said that it showed him there were many forms of consciousness other than rational consciousness, and that these seem to be uncovered one by one. And that's quite an experience. I do not recommend it to anybody, and I hope my writing about these things is not seen as a recommendation. I think I'm very lucky to have survived them, which several of my friends and contemporaries didn't.
The cornerstone condition in Hallucinations is Charles Bonnet syndrome, or CBS. Will you please describe CBS and tell us why you chose to center the book on this condition?
I see lots of elderly people who are hearing impaired or visually impaired but quite articulate and intact intellectually. In general, the hearing impaired get musical hallucinations and, even more commonly, the visually impaired can get visual hallucinations of a complex and dramatic character. These were described in the middle of the 18th century by a Swiss naturalist, Charles Bonnet, and we speak now of Charles Bonnet syndrome. It used to be regarded—when I say "used to," I mean until 1990—as very rare, with only a few dozen cases reported. But it's now obvious that it affects between 10 and 20 percent of people with significant visual impairment. But like all hallucinatory experiences, people are frightened to mention it, and one may only get an account of it when there's a nice, trusting relationship between the patient and the doctor.
[CBS] can be very frightening, as it was for the old lady Rosalie whom I describe. But she was hugely relieved when I could say, "You're not mad, you're not demented, you're not on anything, and this is a normal reaction of your brain to being blind." And I told her about Charles Bonnet, and she was very tickled by it.
She liked to have it named.
Yes, yes—she said, "Tell the nurses I have Charles Bonnet syndrome." I speak about a very different sort of hallucinatory experience she had when she thought she was dying, and I didn't know whether I should add that, in fact, she survived and is now enjoying her 99th year.
That's wonderful to know. I'd also like to explore the section on auditory hallucinations, particularly the cases where people hear voices when they're in serious danger. Are these recognized in retrospect as inner commands, or do some patients continue to believe it was an outside voice?
Well, it may depend on the person somewhat. Freud, no less, described this himself on two occasions when he was in mortal peril: hearing a voice, he said, as "a shout in the ear," saying "this is the end"—and at the same time seeing the words printed in midair. On the other hand, when he heard the voice of his fiancée occasionally when he was a lonely young man in Paris, he wondered if there was something, I want to say, paranormal. He wondered if there was some telepathy, and he would always note down the exact time and try and check. In fact, nothing ever happened.
That must have been very disappointing.
He was perhaps disappointed and relieved. I mention in a different context, in a chapter on epilepsy, a woman who heard a voice—God's voice—telling her to run for Congress. [Laughs.]
And she followed it?
She followed it. And she advertised it, and people thought, "Well, you know, if God suggested it…"
I wonder how she did in the polls.
She did very well. It had always been a strongly Democratic district, but she almost tipped it the other way.