Neurologist Oliver Sacks On The Hallucination That Saved His Life

DAVE DAVIES, HOST:

This is FRESH AIR. I'm Dave Davies, in today for Terry Gross. We begin today's show by remembering Supreme Court Justice Ruth Bader Ginsburg, who died Friday at her home in Washington at the age of 87. We'll listen to an excerpt of the interview Terry recorded with Jeffrey Toobin about his profile of Ginsburg, written as she marked her 20th anniversary on the Supreme Court. At that point, Ginsburg was the senior member of the court's liberal quartet. His profile described how she united the four justices so that they spoke with a single voice. Jeffrey Toobin is a staff writer for The New Yorker and chief legal analyst for CNN. Terry spoke to him in 2013, when his profile of Ruth Bader Ginsburg was published.

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TERRY GROSS, BYLINE: Ruth Bader Ginsburg, before even getting to the Supreme Court, made her reputation litigating cases pertaining to equal rights for women. Would you just run through what some of those important cases were?

JEFFREY TOOBIN: Well, it's important to remember where the law was before Ginsburg started taking these cases in the 1970s. In the 1960s, even the so-called liberal Warren court was happy to approve laws that treated men and women differently. There's a famous case from the early '60s where a Florida law said men were required to serve on juries, but women could turn it down.

And this was a murder case involving a woman who was accused of murdering her husband, and she said, look. It's a violation of equal protection to say that, you know, women, who might be sympathetic to my argument, could get out, whereas men had to be on the juries. And the Supreme Court said no, no, no, women's real function is to be at the home, so it's OK.

And there were a lot of these patronizing laws that treated men and women differently. And Ginsburg really started challenging these laws in the 1970s. One of the first important cases involved an Idaho law that said when someone died, and a man and a woman could both be considered to be the executor of the will, the man should be preferred. And the assumption was men knew more about financial affairs. And Ginsburg wrote the brief in this case - it's called Reed v. Reed - and the Supreme Court unanimously said this was based on outmoded notions of relations between the sexes, and it could not stand under the 14th Amendment to the Constitution.

And with that she went after case after case that indicated usually sort of patronizing laws about whether women were expected to work, whether women could expect to be on juries. And she won 5 of the 6 cases she argued and established precedents that stand even today.

GROSS: You describe her approach in litigating women's rights as incremental, case by case, as opposed to one sweeping case that would say women have to be treated equally in everything, and therefore a lot of laws will just have to be rewritten.

TOOBIN: That's right. And that's very significant, particularly when you start looking at her judicial career because Ginsburg is a methodical person, and she understood that the best way to win at the Supreme Court - or so she thought - and history proved her right, at least in her case - that you don't ask for too much. So she would talk about each individual law on the merits, whether it was a law regarding pensions.

Women were expected to be dependent, so they automatically got a pension when their husbands died, but men were not expected to be dependent, so when their wives died, they had to prove that they were dependent. So she had a man client in that case, and she won that case, again unanimously. And she sort of took on the patronizing assumptions of each individual case, but she didn't ask the court to rule that all differences between the sexes, in terms of how they were treated under the law, were unconstitutional.

GROSS: And she thought that she'd make more progress this way? I mean, was that a practical decision or just a belief that every law should be taken on its own terms?

TOOBIN: That's an interesting question, and I'm not sure I know the ultimate answer to that. But I think she clearly thought as a litigation strategy that when you were dealing with a court of nine men, which, of course, it was in those days, it's better to ask for narrow relief, ask for specific victories in specific cases rather than ask them to rewrite the law of sex and gender in the United States. And so, you know, she did think ultimately that all these laws should disappear, and most of them have. But she didn't think the Supreme Court was the right way to rework all of American law in one fell swoop.

GROSS: So, you know, we've been talking about her incremental approach as a litigator to women's rights. She gave a lecture in 1992 that you write about. It's called "The Madison Lecture," which was delivered at the NYU Law School. And talk about this lecture and what it revealed about her legal philosophy.

TOOBIN: Well, the great women's rights landmark that Justice Ginsburg did not argue as a lawyer was Roe v. Wade, the abortion rights case. And that case was litigated and decided very differently from the way Ginsburg's cases were decided. Roe v. Wade, Justice Blackmun's opinion for the court didn't just declare the Texas law at issue unconstitutional. It said that every law in every state that barred early abortions for women was now unconstitutional.

And Ginsburg in this lecture said that she thought the court was wrong to do that in Roe v. Wade. Ginsburg is a supporter of abortion rights, but she thought the court went too far too quickly in ordering every state in the union. And she thought it set off a political backlash that actually wound up hurting the cause of women's rights. I think that's a very debatable proposition, but I think it is indicative of her careful step-by-step approach that's very different from some liberals, like say, Thurgood Marshall or William Brennan or Harry Blackmun, who wrote Roe v. Wade.

GROSS: And she wanted the legalization of abortion to be - she would have preferred that the legalization of abortion be a dialogue with legislators. What did she mean?

TOOBIN: What she meant is that she thinks that political change in the United States by and large comes from the political branches of government, that real change, substantive change that's enduring needs to come through the democratic branches, through the executive, through the legislatures, through the states and that courts imposing social change is risky and should generally be avoided.

So she has written that in the '70s, many states were liberalizing their abortion laws, and it would have been better for the court to, yes, strike down the Texas law but also let the other states progress politically towards the goal of legal abortion rights rather than just having the court impose it. Now, I think historically that's a questionable assumption. It is far from clear that all the states would eventually have legalized abortion, as Ginsburg seems to assume. But I think again, it's indicative of her cautious approach to how the courts should behave, you know, when it comes to controversial social issues.

GROSS: So in talking about Justice Ginsburg's idea that the judiciary should be in dialogue with the legislature, you know, with lawmakers, she kind of demonstrated that when she wrote the dissenting opinion in the Lilly Ledbetter case that - so why don't you just briefly describe her dissent and the argument that she made from bench kind of directly addressing legislators.

TOOBIN: It was - it's really an amazing story about the power of a dissent in the Supreme Court because she lost the Lilly Ledbetter case. Lilly Ledbetter was a woman who worked at a Goodyear factory in Alabama. And she learned, very much towards the end of her career, that she had been dramatically underpaid compared to the men, the comparable men at the factory. And she sued for violation of Title VII, which prohibits sex discrimination. And she won $3 million at her trial.

But the Supreme Court, 5-4, overturned the judgment, saying that because she filed late in her career, she had violated the statute of limitations. She brought her case too late. Now, Ginsburg in her dissenting opinion said that's ridiculous because she didn't know for years that she had been discriminated against, so how could she have sued? And so - and she said the Supreme Court was interpreting Title VII all wrong.

But what she did in her dissenting opinion was, instead of just addressing the legal niceties, she really called on Congress and said, look; Congress, you can change the law. The Supreme Court is merely interpreting your law, so you should rewrite it and make it clear. And as it happened, that opinion came out in 2007 just as the Democrats had retaken control of the House and Senate and just as the presidential campaign was getting underway.

And Barack Obama and Hillary Clinton took this case, the Lilly Ledbetter case - which had actually been very obscure, not many people were following it - but made it a cause all because of Ginsburg's dissent. And to go forward to 2009, when Obama was inaugurated, the first law that he signed as president is now known as the Lilly Ledbetter Fair Pay Act. And a signed copy of that law stands in Ginsburg's chambers with thanks from now President Obama. And it's just a remarkable success story from a case that Ginsburg lost.

GROSS: You know, in reading your profile of Ruth Bader Ginsburg, I was thinking about the interview I just did with Justice Sandra Day O'Connor. So having, you know, read your article, (laughter) your profile of Ruth Bader Ginsburg, on the same day that I interviewed Justice Sandra Day O'Connor, I found them such interesting contrasts.

You know, Ginsburg devotes so much of her judicial career litigating cases, asking for equal rights, for equality for women. And both Ginsburg and O'Connor faced a lot of discrimination when they were starting off in their legal career. They both found it very difficult to get jobs. And Sandra Day O'Connor talked about how when she got out of law school, 40 law firms or more than 40 law firms turned her down for an interview. And several of them said we don't hire women...

TOOBIN: (Laughter).

GROSS: ...Something that wouldn't even be legal to say today. But when I asked her if those - when I asked Justice O'Connor if those kinds of, you know, discriminatory experiences affected her thinking as, you know, as the first woman justice, Supreme Court justice, she said, well, I can't really answer that. That's the kind of question you'll have to (laughter) try to answer. And she also said she didn't really have to deal with a lot of issues directly related to that. Whereas, it seems like with Ginsburg, the discrimination that she faced and her kind of, you know, life's work are so connected.

TOOBIN: Totally. And, I mean, don't kid yourself. Justice O'Connor (laughter) was very aware of sexist treatment that she received both before and after her appointment to the Supreme Court. And, you know, she, like Justice Ginsburg, had excellent radar for being patronized by her colleagues, most especially Justice Scalia. So I think there is a remarkable - there are actually many more parallels between Ginsburg and O'Connor than there are differences, starting with their academic distinction and difficulties getting jobs.

Also, I think, the affection between them was so real. I remember interviewing Justice Ginsburg once during that period before Justice Sotomayor was appointed, where she was the only woman on the court. And she hated that. I mean, she really didn't like being the only woman on the court.

And she liked the fact - and O'Connor liked the fact that they were different in many ways. You know, here you have O'Connor, this tall, outgoing, rangy Westerner, and Ginsburg, this bookish Brooklynite. And they both liked the idea that it showed that women aren't just one way in the world, that women are complicated and different from one another. Yet it's important that women also be represented. And all - both of them are fierce advocates for more women judges and more women in all positions of power.

DAVIES: Jeffrey Toobin speaking with Terry Gross in 2013 about Supreme Court Justice Ruth Bader Ginsburg. Ginsburg died Friday at the age of 87. We'll hear more after a break. This is FRESH AIR.

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DAVIES: This is FRESH AIR. Today we're remembering Supreme Court Justice Ruth Bader Ginsburg who died Friday at the age of 87. We're listening to the interview Terry Gross recorded in 2013 with New Yorker staff writer Jeffrey Toobin, who'd written a profile of Ginsburg as she marked her 20th anniversary on the court. The story was titled "Heavyweight: How Ruth Bader Ginsburg Has Moved The Supreme Court." But it included something surprisingly personal that Ginsburg had shared with Toobin.

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GROSS: You reprint a letter that she gave you that her husband wrote after he was diagnosed with cancer, 10 days before he died. I want you to describe the backstory to this note. And then I'm going to ask you to read it for us.

TOOBIN: Well, my piece in The New Yorker - somewhat to my surprise - turned out to be in part judicial biography and in part love story. This was one of the great marriages I have ever witnessed in person or, certainly, you know, had the opportunity to report about, in part because Marty Ginsburg and Ruth Ginsburg could not have been more different in terms of their personality. Ruth is shy, retiring, bookish, sort of tries to fade into the woodwork at public occasions. Marty Ginsburg was loud, funny, outgoing, irreverent, a great chef, which he was very proud of. And they complemented each other in a 54-year marriage that to all appearances - and as far as I can tell in reality - was really just a phenomenal love story.

GROSS: So I want you to read the note...

TOOBIN: Oh, the letter. OK. So...

GROSS: ...That her husband left for her.

TOOBIN: Well, Marty, despite his ebullience, was frequently sick. He had testicular cancer even when they were in law school. So you know, his health haunted their whole long marriage. And in 2009, 2010, he had a tumor on his spine. And ultimately, he went for treatment. And it didn't - you know, it didn't take it. And he - the doctors told Ruth and Marty that there was nothing more that could be done. When Ruth was about to take Marty home from the hospital - Johns Hopkins Hospital - she found a note in his drawer of his hospital room. And this is what the note said.

TOOBIN: (Reading) My dearest Ruth, you are the only person I have loved in my life - setting aside, a bit, parents and kids and their kids. And I have admired and loved you almost since the day we first met at Cornell some 56 years ago. What a treat it has been to watch your progress to the very top of the legal world. Two exclamation points. I will be in Johns Hopkins Medical Center until Friday, June 25, I believe. And between then and now, I shall think hard on my remaining health and life, and whether on balance the time has come for me to tough it out or to take leave of life because the loss of quality now simply overwhelms. I hope you will support where I come out. But I understand you may not. I will not love you a jot less. Marty.

He died, as you say, the next week.

GROSS: That's a really beautiful letter. And it just made me think about, like - and I don't know the answers to any of this - you know, like why did he leave a letter and not tell her? Probably - you know, in my mind I'm thinking he didn't want to have a conversation about it. He just wanted to let her know in as clear a way as possible. But he's also - and this is amazing for the husband of a Supreme Court justice. He seems to be proposing the possibility of him taking his life.

TOOBIN: Absolutely. And, you know, even though it is written with so much love, there is a lawyer's precision to it as well, where he is proposing various possibilities, not deciding the issue. And, you know, Marty, as well as being a wonderful husband, was, perhaps, the top tax lawyer in the country. And there is - in addition to the great love of a husband, there is a tax lawyer's meticulousness to it as well. And it is such a rich and full picture in one short letter of a relationship. I have to say, the thing that strikes me about the letter also is two little words: you are the only person I have loved in my life - setting aside, a bit, parents and kids.

GROSS: (Laughter).

TOOBIN: And, you know, in those two little words, a bit, there is a lifetime of complexity you can see.

GROSS: But, you know, the letter also seems to me to be saying - if he's proposing the possibility of terminating his life, he's also saying it's my decision, it's not yours.

TOOBIN: And, you know, it just shows, also, that...

GROSS: And it's my responsibility. It's not yours. Like, the responsibility is not on your shoulders.

TOOBIN: That's right. And again, Supreme Court justices deal with issues of life and death all the time, including issues like when ill patients can end their own lives or be assisted to end their own lives. And, you know, this just shows how those sorts of issues are far from abstract legal controversies for most of us. I mean, all of us have - by the time we get to a certain age in life have dealt with these issues of people who are very sick and don't know whether they want to go on. And it is just - it's so painful. And it's so real. And this just shows how these play out in the messy real world.

DAVIES: New Yorker staff writer Jeffrey Toobin spoke to Terry Gross in 2013 about Ruth Bader Ginsburg as she marked her 20th year as a justice on the Supreme Court. Ginsburg died Friday at the age of 87. After a break, we'll remember the late neurologist and author Oliver Sacks, who's the subject of a new documentary that begins streaming Wednesday. I'm Dave Davies. And this is FRESH AIR.

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DAVE DAVIES, HOST:

This is FRESH AIR. I'm Dave Davies in for Terry Gross. A new documentary about Oliver Sacks, the neurologist and best-selling author, will begin streaming on Wednesday. Sacks was a physician and a professor of neurology at the New York University School of Medicine. His beautifully written books, such as "The Man Who Mistook His Wife For A Hat" examined the mysteries of perception and consciousness by drawing on his observations of his patients. His 1973 book "Awakenings," which established him as a writer was adapted into a 1990 film starring Robin Williams and Robert DeNiro. "Awakenings" was about Dr. Sacks' work treating patients who had survived an epidemic of encephalitis lethargica, commonly called sleeping sickness. Oliver Sacks died in 2015 at the age of 82.

A new documentary, "Oliver Sacks: His Own Life," will be available online beginning Wednesday through the Film Forum and Kino Marquee websites. Terry interviewed Oliver Sacks many times. We're going to listen to their conversation recorded in 2012 after the publication of his book "Hallucinations," which described patients who experienced hallucinations brought on by neurological disorders, brain injuries, medications, fevers, blindness and more - hallucinations that ranged from the terrifying to the transcendent. One chapter, called "Altered States," described his own experiments with mind-altering drugs in the '60s when he was a neurology resident. He said these drugs connected with the reason he wanted to be a neurologist, which was to study how the brain embodies consciousness and the self to understand its amazing powers of perception and distortion.

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DAVIES: Dr. Oliver Sacks, welcome back to FRESH AIR.

OLIVER SACKS: It's good to be with you again.

TERRY GROSS, BYLINE: So at the beginning of your chapter about your own experimentation with altered states, you write, every culture has found chemical means of transcendence. At some point, the use of such intoxicants becomes institutionalized at a magical or sacramental level. What are you thinking of there?

SACKS: Well, I was thinking of peyote ceremonies with Native Americans, but similar ceremonies in Mexico with morning glory seeds - ololiuqui, similar ceremonies in Central America with magic mushrooms, similar ones in South American with both - I can't pronounce it, ayahuasca. And so there's - this seems to happen in every culture at some point.

GROSS: And you write that some drugs, like hallucinogenic drugs, promise transcendence on demand. Is that why you wanted to experiment with them?

SACKS: Well, I think it's one of the reasons. It's probably a little too high-sounding for all of my reasons. I mean, I think I sometimes just wanted pleasure. I wanted to see a visually and perhaps musically enhanced world. I wanted to know what it was like. And I think there's always an observer part, as well as the participant. I would often keep notes when I got stoned.

GROSS: What was the first time you tried a drug that induced perceptual distortions?

SACKS: I think it was in 1963. And I was in Los Angeles, at UCLA, doing a residency in neurology, but I was also much on the beach, on Venice Beach and Muscle Beach. And there, there was quite a drug culture, as there was also in Topanga Canyon, where I lived. And one day, someone offered me some pot. And I took two puffs from it, and I'd been looking at my hand for some reason, and the hand seemed to retreat from me but at the same time getting larger and larger until it became a sort of cosmic hand across the universe. And I found that astounding. I'm strongly atheist by disposition, but nonetheless when this happened, I couldn't help thinking that must be what the hand of God is like or how it is experienced.

GROSS: So you started taking LSD in 1964, and you write that you took mind-altering drugs every weekend for a while. Give us a sense of one of the better experiences that you had that made you want to keep using it.

SACKS: Well, a particular experience was with a color. I had been reading about the color indigo, how it had been introduced into the spectrum by Newton rather late, and it seemed no two people quite agreed as to what indigo was, and I thought I would like to have an experience of indigo. And I built up a sort of pharmacological launch pad with amphetamines and LSD and a little cannabis on top of that, and when I was really stoned I said: I want to see indigo now. And as if thrown by a paintbrush, a huge pear-shaped blob of the purest indigo appeared on the wall. It again had this luminous, numinous quality. I went toward it in a sort of ecstasy. I thought, this is the color of heaven, or this is the color which Giotto tried to get all his life but never could. I thought maybe this is not a color which actually exists on the Earth. Or maybe it used to exist and no longer exists.

And all this went through my mind in four or five seconds, and then the blob disappeared, giving me a strong sense of loss and heartbrokenness. And I was haunted a little bit when I came down, wondering whether indigo did exist in the real world. And I would turn over little stones. I once went to a museum to look at azurite, a copper mineral which is maybe the nearest to indigo, but that was disappointing. I did in fact have that experience again, but when I had it the second time, it was not with a drug, it was with music. And I think music can take one to the heights in a way comparable with drugs. But I think the indigo was my favorite hallucination.

GROSS: So give us an example of a really bad time that you had on a hallucinogenic drug

SACKS: Well, I think the worst time was also a rather puzzling time. It was in '65. I was new to New York. I was sleeping very badly. I was taking ever-increasing doses of a sleeping medication called chloral hydrate. And then one day, I ran out of it. But I didn't think much of this, Though when I went to work, I noticed I was rather tremulous. And that time, I was doing neuropathology. And it was my turn to slice a brain and describe all the structures, which I usually enjoy doing and did easily. But this time, it was difficult, and I hesitated. And I felt my tremor was becoming more obvious.

When the session was over, I went to have a coffee across the road. And suddenly, my coffee turned green and then purple. And I looked up. There was a man paying at the register. And he seemed to have some huge proboscidean head like a sea elephant. I was panicked. I didn't know what was happening. I ran across the street to a bus, got on it, but the people on the bus terrified me. They all seemed to have huge egg-shaped heads with eyes like the eyes of insects.

I somehow managed to get off the bus and onto a train and get off at the right stop. When I got back to my apartment, I phoned up a friend of mine. We'd interned together. And I said, Carol, I want to say goodbye. I've gone mad. And she said, Oliver, what have you just taken? And I said, I haven't just taken anything. And she thought for a moment and said, what have you just stopped taking?

And I said, that's it - the chloral. And so this was the beginning of an attack of the DTs, the delirium tremens, not induced by alcohol withdrawal but by chloral withdraw. It's a dangerous state. I should really have checked myself into hospital, but I didn't. I thought I wanted to go through it with some kindly medical supervision, and I did. But there were many, many terrifying things there.

GROSS: Was it helpful while you were having these nightmarish hallucinations, because of withdrawal from the medicine that you were taking, to know that they were medically induced hallucinations, that you weren't losing your mind and that this was going to end?

SACKS: Yeah, absolutely. When I realized it was medication and not madness, that was a relief so huge that I felt I could sit through the rest of it.

GROSS: As a neurologist, what did you learn from that experience?

SACKS: I - well, I think I learned that one shouldn't be silly. But in particular from that experience, I - there were all sorts of particular, odd visual perceptions. Sometimes, I could not see continuous motion. I would only see a series of stills, and that fascinated me very much. And it made me, in fact, wonder whether the sense of visual motion is an illusion, whether, in fact, we see a series of stills.

I don't think I'd had that thought until I was seeing stills. And with hallucinations, one remembers them, unlike dreams. And on the whole, they're not like dreams because in dreaming, you're asleep. You're only a dreaming consciousness, whereas here you're awake and observing yourself.

DAVIES: We're listening to Terry's interview with neurologist Oliver Sacks recorded in 2012. Sacks died in 2015 at the age of 82. More after a break. This is FRESH AIR.

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DAVIES: This is FRESH AIR. Let's get back to the interview Terry recorded in 2012 with the late neurologist Oliver Sacks after the publication of his book "Hallucinations." A new documentary about Sacks starts streaming Wednesday through the Film Forum and Kino Marquee websites.

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GROSS: So you know how some people say the human brain is wired for God, you know, wired to...

SACKS: Uh-huh.

GROSS: ...To have religion. What's your take on that?

SACKS: I'm very intrigued by the relationship between drugs and religion and hallucination and religion. There's a long chapter on epilepsy, which at one time was called the sacred disease, although Hippocrates said there was nothing sacred about it. Although, he allowed that, sometimes, the symptoms of epilepsy may be visionary.

And in particular, there is a sort of seizure which some people get called an ecstatic seizure, when there will be a feeling of bliss or rapture, a feeling of being transported to heaven, sometimes of hearing angelic voices or seeing angels or communing with God. Experiences like this can happen with seemingly quite irreligious people who have - who don't seem to have an iota of religious disposition. But the experience may be rather overwhelming and may lead to conversion.

GROSS: But it's interesting how often those visions - if we want to call it that - come from something that nowadays would be diagnosed as a disorder and, in fact, are disorders like epilepsy or schizophrenia.

SACKS: Yes. Well, certainly, I think there have probably always been visions and voices. And these were variously ascribed to the divine or the demonic or the Muses. The medicalization of hallucinations really only occurred in the 19th century. And following that, people became, I think, very much more anxious about hallucinations and secretive and ashamed. And the subject was much less discussed. I think hallucinations need to be discussed. There are all sorts of hallucinations, and there are many sorts which are OK, like the ones I think which most of us have when we're in bed at night before we fall asleep, when we can see all sorts of patterns or faces or scenes.

GROSS: If you're just joining us, my guest is neurologist Dr. Oliver Sacks. His new book is called "Hallucinations," and it's about medically induced hallucinations, naturally occurring hallucinations, like between waking and sleeping, and hallucinations that are side effects of drugs, hallucinations that are caused by various medical conditions.

SACKS: Can I add to your list? Hallucinations which are caused by real-life experiences, such as bereavement.

GROSS: Yes. I'm glad you mentioned bereavement. And that is such a common form of hallucination, where, you know, you've lost somebody who you love and you think you've seen them or heard them say something. And when that happens, I think it's fair to say it feels like a visitation. How would you describe that?

SACKS: Yeah. Well, someone dies. There's a hole in your life. And that hole can be briefly filled, I think, by a hallucination. Typically, the bereavement hallucinations - which are common; something like 40 or 50% of bereaved people get them occasionally - are often felt as very comfortable, comforting. And they may help them through the mourning process. And when one has mourned fully, they disappear.

GROSS: How, as a neurologist, would you interpret those hallucinations?

SACKS: Well, with any hallucinations, if you can, say, do functional brain imagery while they're going on, you will find that the parts of the brain usually involved in seeing or hearing - in perception - are, in fact, being active, have become super-active by themselves. And this is an autonomous activity. This does not happen with imagination. But hallucination, in a way, simulates perception, and the perceptual parts of the brain become active. And - but, you know, what else is going on - there's obviously a very, very strong, passionate feeling of love and loss with bereavement hallucinations. And I think intense emotion of any sort can produce a hallucination.

GROSS: I'm just curious. Like how - how do you do functional brain imagery of somebody who has had a hallucination? I mean, they're probably not hooked up to the FMRI when they're feeling like they had this visitation from a lost loved one.

SACKS: Well, there, it will be difficult, because hallucinations like this are rare and sporadic and unpredictable. But there are other people - and I am especially interested in this, because I've worked in old age homes for the last 40 years or so, and I've seen many, many elderly people who are intellectually intact but have impaired vision or hearing have visual or auditory hallucinations on this basis.

The visual one they call Charles Bonnet Syndrome, and people may see faces. They may see landscapes, patterns, musical notation for hours a day. And in this situation, you can have someone inside a functional MRI, and they can, say, raise a finger when they are hallucinating. You may then say to them, you were hallucinating faces. They may say, how the hell do you know? And you will say, because the face recognizing part of your brain suddenly became very active.

GROSS: Wow.

SACKS: And it is this sort of thing, especially with patients with Charles Bonnet Syndrome, that you can plot, you can map the brain by the sort of hallucinations people get.

DAVIES: We're listening back to an interview with neurologist Oliver Sacks recorded in 2012 after the publication of his book "Hallucinations." Sacks died in 2015. We'll hear more after a break. This is FRESH AIR.

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DAVIES: This is FRESH AIR. We're listening back to an interview with neurologist Oliver Sacks, who died in 2015. A new documentary about Sacks starts streaming Wednesday through the Film Forum and Kino Marquee websites.

(SOUNDBITE OF ARCHIVED NPR BROADCAST)

GROSS: You write in your book "Hallucinations" about an auditory hallucination you had that really might have saved your life. You were mountain climbing, and you had injured your foot or your leg. And part of you just wanted to just, like, slow down, sleep. But then you heard a voice, which said what?

SACKS: Well, the impulse to sleep - I'd torn off most of the thigh muscles and the knee was dislocating backwards. And at one point I got quite shocked and thought it'd be nice to have a little sleep. And the voice said, no, that would be death. Go on. You've got to keep going. Find a pace you can keep up and keep it up. And this was a very clear, commanding voice. It was a sort of life voice and it was not to be disobeyed.

GROSS: And so you kept going in spite of the horrible shape that your leg and knee was in.

SACKS: Yeah. I was sort of lowering myself down with my arms. I had splinted the leg as best I could with an umbrella stick and my anorak, which I tore in two. Incidentally, I thought that was going to be the last day of my life. And it had every prospect of being, but I was found at twilight by two hunters. This was in north Norway. But that voice was crucial for me.

And I've heard many other stories like this. One of them was from a young woman who was brokenhearted after a love affair and determined to commit suicide. And she had a bottle of sleeping tablets and a tumbler of whisky to wash them down. And she had raised the tablets to her mouth when she heard a voice saying, don't do that. I wouldn't do that if I were you, you won't always be feeling the way you're feeling now. It was a man's voice. She didn't recognize it. She was fairly startled. She said, who was that? Who was that? And she said a figure materialized in a chair opposite her for a few seconds, a figure in 18th century dress that vanished. But she feels that hallucination saved her life. And I think her story is not that uncommon. Nor mine, for that matter.

GROSS: Whose voice did you hear? Was it your voice, a stranger's voice?

SACKS: Not my voice. I often hear my voice. I am always sort of cursing or muttering to myself. But this was a very clear, assured voice, not a voice I recognized but a voice I trusted, which I suppose I realized came from some part of me because there's no other place it could've come from.

GROSS: It seems to me you've had a very neurologically eventful life.

(LAUGHTER)

GROSS: Honestly, like you've had migraines from like the age of four and, you know, you heard the voice when you were mountain climbing and would've died had you not kept walking in spite of a severe leg injury. You've had spinal pain and, you know, wanted to understand the, you know, nerve causes of that. You've had visual disorders. And it just seems like you have experienced so much, which I know has been useful to you as a doctor, but it seems like a lot for one person to go through.

SACKS: Yeah, I...

GROSS: You've lost your sight in one eye because of cancer, and that started out with all kinds of distortions.

SACKS: Yes. Well, it has been a lot in a way, but I feel I'm lucky. I'm close to 80, and I'm still in fairly good shape, especially if I can go swimming. I limp a bit on land, but I'm powerful in the water. And it's true I've only got one eye now, and the other one needs some surgery. But I manage. I suspect that most people may have quite a lot of neurological things to which they don't pay much attention. I think I probably differ from others only in having paid attention to things.

GROSS: Well, Dr. Sacks, it's just such a pleasure to talk with you. You're always so interesting. I thank you so much for coming back to our show.

SACKS: Well, thank you so much. And I always love talking with you. And I love the way you you keep me focused, or you try to keep me focused.

(LAUGHTER)

SACKS: Although I'm incorrigible.

GROSS: You're great.

DAVIES: Terry Gross recorded that interview with neurologist Oliver Sacks in 2012. He died in 2015 at the age of 82. A new documentary, Oliver Sacks: His Own Life," will be available online starting Wednesday. You can find it at filmforum.com as part of their Virtual Cinema series and at kinomarquee.com.

On tomorrow's show, I'll speak with Forbes magazine journalist Dan Alexander, who's been reporting extensively on President Trump's finances. His new book is "White House, Inc.: How Donald Trump Turned The Presidency Into A Business." I hope you'll join us.

FRESH AIR's executive producer is Danny Miller. Our technical director and engineer is Audrey Bentham, with additional engineering support by Charlie Kaier and Adam Staniszewski. Our interviews and reviews are produced and edited by Amy Salit, Phyllis Myers, Sam Briger, Lauren Krenzel, Heidi Saman, Therese Madden, Thea Chaloner, Seth Kelly and Kayla Lattimore. Our associate producer of digital media is Molly Seavy-Nesper. Roberta Shorrock directs the show. For Terry Gross, I'm Dave Davies.

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