Sacks: In 1967-68, when I was writing Migraine, I was somewhat horrified by the current papers and publications on the subject, but in '68 there was a book that was an epiphany for me, A.R. Luria's The Mind of a Mnemonist. I read the first few pages thinking it was a novel, because it has all the power and poignancy and pathos of a novel. But then I realized it was a case study, one of the most detailed I'd ever read. Luria himself, in his autobiography, talks about his feeling that the art of observation and description that was common to the great neurologists and psychologists of the 19th century is almost gone now and must be regained. And he had regained it himself, and I've tried to regain it. One needs statistics — one couldn't have indicted the evils of smoking without such statistics — but one also needs single case histories which are very detailed not only on the pathology but on the person. 

MT: In terms of style, you really strike me as one of the masters of the footnote. Yours are more like that great one in William James' The Principles of Psychology — where he tells readers how to go get a lamb and crack open its skull to examine its brain — whereas most scientific footnotes simply refer you to other studies. Is that a conscious thing? 

Sacks: I don't think of them in terms of literary style, but I have multitudes of thoughts bursting on me and I fear they would explode the argument or description, so excursions of every sort can be made with footnotes. A good friend of mine, Jonathan Miller, says I suffer from commentarrhea. But I find it difficult to write without footnotes. In one of my books, Island of the Colorblind, footnotes end up taking up a third of the text. 

MT: After a lifetime of doing this kind of research, were there still things that surprised you about hallucinations? 

Sacks: Quite a lot of them. A single small one which intrigued me was people who have hallucinations of musical notations, though typically they can't sing or play what they see because it's too elaborate and complicated. I had hardly heard of near-death and out-of-body experiences, but I am writing more about them now. I was fascinated about how rich hallucinations of smell can be, and I am fascinated by the way that they can extend beyond imagination: The variety of faces one may see in hallucinations are endless. The brain's ability to invent comes up very strikingly in hallucinations. 

But something just crossed my mind. This is a footnote to what I was saying. I mentioned I had a visual migraine last night. It was a strong one and I was very struck by an almost blinding violet color. All the colors of the spectrum were there, but this blinding violet seemed to be beyond any violet I've ever seen. And one knows the retina can respond to ultraviolet, although normally the lens, which is a bit yellowish, prevents anything from getting in. But if the retina can respond to it, the brain can respond to it, and I wondered whether, in the migraine-spectrum being concocted by my brain, it was being extended a little bit into the ultraviolet. I don't know whether it is a ridiculous thought or not. 

MT: Are you working on a new book? Do you have a new obsession? 

Sacks: I don't know whether I have a new obsession or not. I wonder whether, instead of long, extended case histories, I might put together a book of them that are only a paragraph or two in length. I must have heard hundreds, even thousands of odd stories and observations. I have been wanting to put together some essays on memory and creativity. I've also wondered about some non-medical writing. I've been an assiduous keeper of journals, especially travel journals, since I was 14, and I would wonder about putting some of those together. So I'm actually not quite sure what comes next. 

Baynard Woods writes for City Paper in Baltimore where this piece originally appeared. Send comments to letters@metrotimes. 

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