A passion for understanding: Oliver Sacks on hallucinations and other neurological curiosities

Posted by:


Today, neurologist Oliver Sacks — who gave the classic talk, “What hallucinations reveal about our minds,” at TED2009 — revealed in The New York Times that he has terminal cancer. In a beautiful essay, he writes, “It is up to me now to choose how to live out the months that remain to me. I have to live in the richest, deepest, most productive way I can.”

Back in 2009, Sacks invited the TED Blog into his office for an interview, just before his talk went live. He hosted us for over an hour, discussing his book on vision and the mind and giving details of the visual hallucinations he experienced after losing vision in his right eye — from the tumor which ultimately metastasized nine years later.

Dr. Sacks proved to be as fascinating as all rumors indicated, with an office full of his hobbies and interests — from his expanding geological collection to an antique crystal radio made in 1915 — it was a little oasis for the curious mind.

Well, first of all, it’s lovely to meet you. I think you’re probably very accustomed to people being impressed by your work.

And disappointed when they meet me in the flesh. (Laughter)

What was TED like for you?

It was a wonderful sort of gathering. You never quite knew what was going to happen next. And there were so many creative people of every sort there. I think it was really rather astounding.

You’re currently writing a book on hallucinations …

Well, it’s not just hallucinations, but they’ll be about half the book. The current title is The Mind’s Eye and it’s about vision and visions and visual memory, as inspired in the first place by people coming to see me as patients or writing letters. I get something like 200 letters a day, of which I answer about 30. I can’t answer them all. But, I really feel very privileged because people write to me from all over and tell me interesting things that are going on with them. And, in a strange way, as a neurologist, I think I sometimes get my ideas in this way. In health, things are seamless. You would have no idea that color and motion and texture and depth are separately processed in the brain, because what we perceive, finally, is a whole visual world. But I often communicate with people who’ve lost just color perception or lost just stereo vision, which shows how things can go wrong. So yes, the hallucinations fascinate me, but mostly because they show how the brain works in everyday life.

But also, as a physician, I need to be in a position to reassure people with a particular sort of hallucination that they’re not going mad. They’re not losing their mind. And the word hallucination has bad vibes. It immediately suggests something ominous. It’s sort of a pity we don’t have another word. Although, curiously, I was just reading an 1824 book called The Philosophy of Apparitions and in those days “apparitions” was used, or “phantoms.” They’re both nice words. You talk about phantom limb, you don’t talk about a hallucinatory leg. Somehow, a phantom limb sounds better.

You wrote this book A Leg to Stand On and it was about your experience of having the leg, but having the feeling of leglessness — the opposite of phantom limb. And now you’re writing many years later about hallucinations and I’ve been told that you’re having some hallucinations yourself, in fact.

Well, I don’t have much vision in the right eye. I had a tumor in the right eye, which has been irradiated and lasered, and I hope laid to rest. But that has taken most of the retina with it on that side and so I’ve only got a little sliver of peripheral vision and the rest is a great black area of scotoma, which changes its appearance as soon as I look up at the ceiling — then it camouflages and turns white, or turns blue if I look at the sky. And it tends to be full of tiny things, of tiny letters and numbers, which look rather like incised hieroglyphics to me, along with a few other simple things like chessboards and spirals and spiders’ webs. So I’m just having fairly simple geometrical hallucinations. I’m not having faces or anything like this, and don’t expect to have them.

But they’re very easy to separate from reality?

Yes. Mostly. Although occasionally, I confess, certainly in the early days, when I would perhaps go in to someone’s apartment, I might think, “What an interesting … what a curious stippled wallpaper.” And I’d mention this. And the person would say, “What do you mean stippled? It’s not stippled.” So, now I realize the stippling comes from me, from the visual areas of my brain which area trying to fill in this rather large blind spot.

But with hallucinations that are complex and more plausible and in context, then it can be different. that are complex and more plausible and in context, then it can be different. There’s a historical description, from the Charles Lullin in the 1750s where he first saw a gigantic wheel in mid-air and he thought, “Oh, so that’s a hallucination. We don’t have gigantic wheels in mid-air.” But then his granddaughters came to visit and he said, “Who are these handsome young men with you?” and they looked downcast, because there weren’t any handsome young men. But, there could have been. They were sufficiently plausible.

And it can go the other way around. I got a story about someone who’d become very used to his hallucinations and very cool about it. He lived on the 19th floor of an apartment building, and one day he saw someone hovering outside his window. You don’t have someone hundreds of feet off the ground, so he thought it was a hallucination. And the hallucination apparently waved at him. He paid no attention. And then of course, the window cleaner talked to the person next door and said, “What’s wrong with him? I waved at him and he didn’t respond.” So there, reality was mistaken for a hallucination.

Things like this conjure up, for example, images of that movie A Beautiful Mind, based on the life of John Nash, where the lead character has to learn to recognize what is reality and what is hallucination.

Well, first, that film is quite a long way from the book. There’s a certain distinction from reality — although I know John Nash a little, and, he was quite approving of the book and the film. On the whole, visual hallucinations are not nearly as common in schizophrenia as voice hallucinations. But, the sort of hallucinations I’m dealing with here are very different from psychotic hallucinations. Psychotic hallucinations seem to be often intimately connected with what one is thinking or feeling and they may address one and command one, or accuse one or seduce one. his is unlike the sort of hallucinations that blind people can get, when the brain is not getting its normal input but the visual parts of the brain still stay active and may develop their own output. The people who have these sorts of hallucinations think they see them on a screen or possibly their room, but they don’t interact with the hallucination. When I talked at TED I think I described one patient with this sort of hallucination. I said to her, “Is it like a dream?” And she said, “No, it’s not. It’s like a movie. A rather boring movie.”

So, one of the things I was saying at the beginning and I have to illustrate this, is that I’m writing about something that is a rather different thing than psychotic hallucinations such as John Nash’s. The next book will be about that. Maybe.

People often use say that I study mental illness. But I am not a psychiatrist; I study people with neurological problems and not primarily mental illness as such.

You have still brought to people these stories of people who are different from them, who either perceive differently or think differently. Your work seems to have helped people understand what it is like to be different. Is this something you intended to do? Was there an attempt to destigmatize your patients on your part?

This has not been an explicit thought or message and I don’t feel I have “messages.” But, I’m a describer and I want to share experiences, and I think, especially to see beyond a diagnosis to what the whole person is like.

This is clear with something like Tourrette’s syndrome, which was seen as extremely rare in the 1960s. I first saw a patient with Tourette’s in 1971, and the day after him I sort of saw three people on the streets of New York and another two the next day. And I thought, “If my eyes are not deceiving me, this must be a thousand times commoner than it’s supposed to be. And, why haven’t I noticed this before?” There’s always a first time when your eyes are opened and then suddenly you see things all around you, and in all sorts of different ways.

But, “destigmatize” … I don’t know whether you saw it but I have a piece in the current New York Review of Books about mental illness, which is actually the first time I’ve ever written an essay on this. I never use the word “stigma,” as I never use the word “power.” I don’t tend to have this sort of political-sociological vocabulary, but I think very much in terms of needs and obligations. I don’t think I’m motivated too strongly by stigmas. I think my general feeling is sort of sympathetic and appreciative and respect for everyone. I hope that diffuses. But at the same time, that’s not the intent of my writing. It’s not intended to destigmatize. It’s intended to present people in their richness, as a whole, which may include a diagnosis or two. What I want to say, also, is that the “who” is greater than the “what.”

So for you, it’s more about the love of the story and a love of people?

There’s always feeling. For example, with this nice lady here (as he points to a photograph over his desk), see she’s paralyzed on one side — she had a stroke and severe aphasia — I was her doctor for 20 years and I really loved her. She was such a gallant person. And I would not only see her as a patient in hospital, but I would go for a walk with her her outside, we would go shopping together, or to a coffee shop. When I wrote about her in the New Yorker, I think saw her and portrayed her as a complete human being, which I always try and do.

And this is Clive (pointing to another photograph on his bulletin board), the man who had amnesia whom I wrote about in Musicophilia. And this is a man who had Tourette’s syndrome, who I wrote about. So although I wouldn’t care to be a doctor to my friends, I can become friendly to my patients. Although, this is made pleasanter by the fact that the formality is there as well. But, I’m moved by feeling certainly as much as intellectual curiosity, but not by an agenda.

I think it’s very interesting that the pictures above your desk are those of your patients.

And some of my heroes. There’s Lynne Cox, who was a great marathon swimmer and also swum the Antarctic and I have a passion for swimming too. And of course, Temple Grandin from An Anthropologist on Mars. And there’s some friends there too. There’s Stephen Jay Gould and (Francis) Crick. And a lemur, because I’m very fond of lemurs.


Did you know there’s a lemur colony in North Carolina? It’s most amazing. And I hope they survive because Madagascar is so threatened. Anyhow, I must get back to hallucinations. I very easily distract and I distract others and often my distractions get turned into footnotes.

These little things oddly, people are often very interested to know. You’re a bit famous, with an amazing fan base for a neurologist. How do you feel about having this pretty huge audience?

It wasn’t intended. But then, it wasn’t unintended. With my first book, I worked in a migraine clinic, I saw more than a thousand people with migraine. I’ve had migraine myself since I was three or four. (I had visual migraine, which is another reason I’m interested in all things visual.) A lot of understanding develops when one first sees a patient. They stumble, they don’t know what’s relevant, they tell a story, you fill in other stories and between you, you begin to arrive at something. At that time I began to read a whole lot of technical pieces about migraine, and I read something that inspired me. It was a late 19th century book called Megrim which was the old word from the 1860s, and that book had every sort of dimension — sociological, physiological, human. And I thought, it’s a century later, but we still need a book like this. And I thought, it’s the 1960s, but we still need a book like this. I’m very attracted to the full, almost novelistic descriptions we had in the 19th century. I think doctors and scientists naturally work well with this sort of format. So I wrote my first book, Migraine, in this sort of vein. And when it was published, it it got equally noticed by scientific readers and by popular readers. I think migraine turns out to be unexpectedly interesting–but then I think everything turns out to be very interesting, relevant to the human condition. You may not actually have migraine, but we all have something, and it’s perhaps about having something, living with something and dealing with something.

I was amazed when The Man Who Mistook His Wife For a Hat came out. So many people wrote to me about Jimmy, the Lost Mariner, or later about Temple Grandin. And one feels one has sort of opened a whole forum for discussion, which is among other things what I want to do in my new book, because I’ve seen many patients with visual hallucinations living in terror and holding it as a secret. They’re afraid they’re going crazy or losing their mind and 99 times out of 100 there’s something benign about hallucinations. And so one wants to open it out and in a way say, “It’s ok. “ This is exactly what happened in my Hat book. I wrote about musical hallucinations there, and this was mentioned in the newspaper column “Dear Abby”. People wrote to Dear Abby saying, “Since Dr. Saxe’s book came out, I realize this is what I have and I never mentioned it to my husband.” Dear Abby asked me if I would like to write something in her column, so I wrote a little tiny piece, which was more or less reassuring and clarifying. And since then, I have had a non-stop torrent of letters from people all over the world who have musical hallucination, and now I’m getting the same with visual hallucinations.

And while on this popular reader, there’s a phrase, which Nathaniel Hawthorne uses in the preface to his Twice-Told Tales where he says that it’s his hope to establish an intercourse, however imperfect, with the world. And, with me, I’m a rather shy person and I don’t readily open conversations or speak to people, but my way of speaking to people is writing and their way of speaking to me is letters. I’d say I’ve written a dozen letters this morning. Letter-writing gets me in the mood for book-writing. To some extent, a book is like a letter to everybody, or rather a letter to anybody who might be interested.

On your website, there’s a quote from you on A Leg to Stand On where you say the you felt that this was something you needed to do to understand and get through that time …

And somehow defuse it.

So, the hallucinations don’t seem to be quite as traumatic, but is there also a feeling that you want to explore them and the book is your way?

Yes, I’ve kept a visual diary since my eye problem blew up a few years ago. These are my drawings some of the broken letters and things. And — oh yes, I got myself a piano teacher after a break of 62 years and so I was studying sheet music, really examining the bar clef carefully, and since that has happened, my blind spot has often been filled in with little showers of flats and sharps.

I have a few other visual problems, for example, since I’ve lost the sight of one eye, I’ve lost depth vision. I’ve now accommodated to some extent, but at first I did embarrassing things, like I would pour someone a glass of wine and miss the glass. But this description of my own experiences is only a fraction, of this book.

Incidentally (showing a long, white scar that runs around his knee and almost all the way up the leg), that was the original scar from A Leg to Stand On and it’s going to be re-opened because I’m due to have total knee replacement in two weeks. I’m going to have spinal anesthesia for the operation. I much prefer to be awake partly because I’m inquisitive, and I hope they have a mirror so I can watch the procedure. I would like to see what’s going on. I don’t like the idea of being passive. If something happens to me, whether it’s a tumor in my eye or an operation on my leg, I somehow want to explore it. Now, when you have spinal anesthesia, it’s very strange, and I don’t mean a little epidural, I mean a good, old-fashioned spinal block.I actually wrote in an Afterword to my Leg book that I thought my book would be unintelligible to people unless they actually read it while under spinal anesthesia. What lies below your waist is a pair of legs, anatomically, but you feel like, “Those have nothing to do with me.” So that’s like the negative phantom thing, which I had.

It is very interesting, your attitude towards the things that are happening in your own body, because it’s one thing to make a case study of others’ lives, but you’ve also made one of your own, rather than getting scared.

No, I do get scared.

But this is how you deal with it?

It serves maybe to put a certain intellectual distance there. But still, I was absolutely terrified with this melanoma at first. I didn’t even know one could have ocular melanomas, let alone that they were much more benign than other sorts. When it was diagnosed, the surgeon brought out a model of an eye and he put in it something that looked like a little, shriveled, black cauliflower. And my immediate thought was that, in England, when a judge is going to pass a death sentence, he puts on a black cap and I saw this thing as the equivalent. I thought, “It’s my death sentence.”

But still, as a neurologist I can’t help that even in my own life, I am always on the lookout for information, for material. We all are. When I first met (Francis) Crick in ’86, he seized me by the shoulders, he sat me down next to him at dinner and he said, “Tell me stories.” And he wanted clinical stories, and stories of patients. And each story would set off this sort of explosion of hypotheses and theories and suggestions for research. Crick was a wonderful thinker. He was a man who loved thinking, whether it was in physics or chemistry or anything else. But he was a bit short of material, and here am I, fresh from the clinic. So, he would pump me for stories. But he would provide wonderful, wonderful sort of suggestions and hypotheses. I don’t know how much of a theoretician I am myself, although meeting him and knowing him has turned me much more towards neuroscience that I was 20 years ago. I’m now surrounded by papers on MRIs and visual hallucinations. I’ve also had my own brain MRI’d.

Did you?

Twice. Once in regard to visual phenomena and once in regard to musical imagery and memory. You know, I have direct access to this brain. I don’t have direct access to anyone else’s mind.

So before we round up, I’m peering over at your master copy of The Mind’s Eye and I’m wondering if you could give me a run-through of the various little things that appear in the book.

The order keeps changing. The opening piece, I think, will be a piece about a woman who had been, in effect, one-eyed all her life, but who acquired binocular vision at the age of 50. I found this incredible scientifically, and she was a neurobiologist, who knew this shouldn’t happen. So her wonderful visual diary, about a world suddenly enriched by depth and made very beautiful to some extent finds an echo in mine, towards the end of the book, when I, who have always seen the world in stereo begins losing that.

The biggest chapter, the centerpiece of the book is about the experiences of the blind, the visually impaired, who are the last people you would think would be seeing things.

We never realize the miraculous number of orchestrations that have to happen for us to experience the world. For example, there are something like 50 visual sub-centers and all of them have to talk with each other and be orchestrated, and there’s no conductor, they all orchestrate themselves.

This interview was originally published in September 2009. It was updated in February 2015.