5_two_ways_of_being_transcription

#5  - Two Ways of Being - Transcription

Oliver Trace:[00:00:00] We've spoken a lot about the right hemisphere and the left hemisphere, assuming that there are differences in the two hemispheres. I say assuming; we believe it to be the case. Me, largely because of what you have written, but also because I believe it's something that people can connect with fundamentally without having to even say right hemisphere or left hemisphere. There are these two ways of being that exist both independently and dependently within us and come together to form a whole. In your book, it seems that you are suggesting that these two different ways of being are reflected in the way in which the two hemispheres behave. What I'd like you to do is just begin with why study of the two hemispheres was dismissed.

Iain McGilchrist:[00:00:53] A lot of nonsense was talked, and that nonsense became more gross as it got taken up by management seminars instructing people on how to use their right brain. Some of this was well intentioned. Perhaps a lot of it was. But the trouble is that a lot of what was conveyed was wrong. For example, the principle was that the right hemisphere was somehow just touchy feely, but not very reliable. It might be, you know, a bit creative, but it really wasn't doing any hard thinking. Whereas the left hemisphere was the rational one and the one that had language. Now, I mean, these ideas sprang up in the wake of some fascinating research done on split brain patients. Just to explain what a split brain patient is: it's the popular term for somebody who had a procedure called commissurotomy, which is a cutting of the corpus callosum, the band of fibres that connects the two hemispheres at their base. Why was this carried out? Because people who had intractable epilepsy were spending perhaps most of their life in a semi-conscious or unconscious state because of continual seizures spreading across the entire brain. And it was reasoned that if you could just cut the main connections between the hemispheres, then if the exciting influence (I use the word exciting in the sense of electrical excitation) started in one hemisphere, it wouldn't spread to the other, so the person would remain conscious, at least using that hemisphere, and nobody really knew what would happen.

Iain McGilchrist:[00:02:36] And this was pioneered in Caltech in the 60s, and it led to some fascinating results. I mean, one was that people were much less disturbed or different after this operation than people had anticipated. What would happen if you divided their brain? The answer was not terribly much, at least after a few months had passed. Initially, there was some disorientation. Immediately after the operations sometimes people found themselves with conflicting wills, conflicting values. One half of the brain would want to read a book, the other would close the book and put it down. One hand would go into the cupboard to pick out a dress, the other hand would take it, put it back and select another one. And there's a story of a man who went to embrace his wife with one hand and pushed her away with the other. These are the sort of things that arose in the early stages and are in themselves, I suppose, quite interesting. But basically after a few months they all settled down. But they then left people who were, to all intents and purposes, entirely normal. I mean, you could have dinner with them, you could go on holiday with them. You probably wouldn't know that they were very different from anyone else. But it was possible to do experiments with them in which you could isolate one hemisphere at a time and find out what it saw, what it understood, how it approached things.

Iain McGilchrist:[00:03:55] And that was just fascinating. And it was from that that these rather gross ideas began to emerge after they had filtered down into popular culture. But with time, people realized that none of these things was right. For example, there are big contributions to language by the right hemisphere. There are big contributions to visual imagery by the left hemisphere, and there are big contributions to reason by the right hemisphere, which it turns out, is actually far more reliable and in touch with reality than the, if you like, “doolally” left hemisphere. So it's exactly the opposite of what people used to say. The left hemisphere knows how to carry out certain procedures, but left to itself is essentially deluded, seriously deluded and hallucinating and really completely unreliable as a judge of reality. With somebody with the split brain, you can deliver information to one hemisphere only at a time. That can be done visually, for example, by flashing something to the right visual field, which goes to the left hemisphere, or flashing something to the left visual field and going to the right hemisphere.

Oliver Trace:[00:05:09] One of the experiments which I found very, very powerful, is asking patients to draw shapes. How do you ask them to - do you flash an image of a flower and then ask them to draw a flower, to one hemisphere versus another?

Iain McGilchrist:[00:05:28] You're referring to the research by Nikolai Nikolaenko in what's now Saint Petersburg, and his team, which was done rather differently with intact individuals. But it is possible - don't try this at home, as they say - but it is possible to, as it were, suppress or switch off one hemisphere, relatively speaking, for short periods of time. Nowadays that would be done using transcranial magnetic stimulation, which I mentioned before, which can be a held handheld device, it's so simple, that administers a very strong magnetic field immediately under the area of the brain where it's positioned, and depending on the frequency, it can either stimulate activity in that area or repress it. So you can do that. In his case, what he was doing was looking at patients who'd had ECT, a treatment for depression, electroconvulsive therapy, which was applied in this case, alternately, sometimes to the left hemisphere and sometimes to the right hemisphere. Now, this procedure, which sounds barbaric and has had a very bad press because of things like One Flew Over the Cuckoo's Nest, is actually very important. I mean, it probably was a bit barbaric in the way it was administered 50 years ago, but it is now a very important procedure for helping people with intractable depression. And while they have it, they are anesthetized, so they don't know anything about it, and they wake up and they can feel extremely much better, even after just a few treatments. So let's not get that wrong. But in any case, in his experiments, he would have the situation where somebody had temporarily had their left hemisphere shocked. And for about 15 minutes afterwards, 15 to 20 minutes, that hemisphere is not really contributing. The other hemisphere is. So with these patients, he could just, in these narrow windows, ask them to carry out a task: draw a flower, draw a tree, draw a cube, draw a person. The results are extraordinary.

Oliver Trace:[00:07:41] And what are the results? Let's say we've got the right hemisphere inhibited.

Iain McGilchrist:[00:07:45] Well, if you've got the right hemisphere inhibited, only the left hemisphere is at work. And sometimes you see something called neglect, which is that everything that is not to the left of the midline is simply ignored. As far as the left hemisphere is concerned, it simply doesn't exist. What that illuminates is that the left hemisphere is only interested in one bit of space, the right bit of space, which is the bit in which it goes to take things. Because what we haven't described yet is that the left hemisphere subserves the predator instinct. It's the bit that enables us to latch on to something that we already know is of interest, pay very precisely focused, narrow beam attention and get it. It's the bit in us that controls the right hand and controls that bit of language. Not all of language, but that bit with which we say we've pinned something down. We've got it. We've grasped it. So that is the left hemisphere's take. If you have a stroke in the right hemisphere, then the left hemisphere, which is all that’s left, gives you only half a world. And patients after this will not pay attention to people on the left. They will not apparently see them. They will not apparently hear them. If they have a book, they will only read the right hand page, or even sometimes the right hand ends of the sentences. It's not that there's anything wrong with their vision, not at any level between the eye and the visual cortex. All is working. But they're just not attending to it. As far as they're concerned, it doesn't exist. If you're at all interested, there is a fantastic clip on YouTube of a dog that's had a right hemisphere stroke, and it's eating from a bowl, and the bowl is full and it eats only the stuff on the right, and then goes away, and the bowl is then turned round and the dog goes, oh, it comes back and eats the other half.

Oliver Trace:[00:09:33] Before when you were saying you have the electric shocks and one side is disabled momentarily, are then patients asked to draw a flower? 

Iain McGilchrist:[00:09:41] In these particular experiments by Nikolaenko, they were asked to do certain drawing tasks. And it's extraordinarily vivid because when the right hemisphere alone is drawing a flower, it draws the whole living, flowing shape of the flower. And you see that as a recognizable flower. In some senses, it looks even more alive than the one drawn previously by the same person before they'd had the ECT. But when that person's left hemisphere only is operative, they draw something that looks like a button. It's entirely geometrical, symmetrical, stereotyped. And when it comes to people, they draw rhomboids and stick people and things like that. And interestingly, they also lose the sense of depth in space. So instead of seeing things as having spatial depth, they see them as flattened. So when they draw a cube, most people are practiced at drawing a cube and know how to draw a cube, perhaps not very well, but to draw it in perspective, and that you know that in drawing a cube you can draw 1 to 3 sides that you can see, but the maximum number of sides you can see at any time is three. But after this they draw not what they see, but what they know. They draw a thing with six sides, which is what a child before it learns perspective would do if asked to draw a cube. So they're actually losing sense of the depth of space.

Oliver Trace:[00:11:10] And the symbol is replacing the reality.

Iain McGilchrist:[00:11:12] The symbol, a sort of symbolic, much reduced representation of the thing replaces the thing itself. Now, why that is important may not seem obvious. The thing that is probably most distinctive about the difference between the hemispheres and most catastrophic for us, if you rely only on what our left hemisphere tells us, is that if I can put it this way, the left hemisphere offers a map where the right hemisphere offers us a view of the territory or the terrain as I like to say, because the terrain is where we live.

Oliver Trace:[00:11:46] Let's give a brief story while we're there of the map versus the reality of the lived world. Because you tell a story yourself, which I think is a good example of this. And most would connect with how it has meaning today, and I'm sure we'll have their own versions where there's a woman whose husband or partner or brother…

Iain McGilchrist:[00:12:13] Yes, I can tell that story.

Oliver Trace:[00:12:14] Yes, so perhaps you could tell that story.

Iain McGilchrist:[00:12:16] Yes. Perhaps I should also tell the story about the experiment which illuminates it.

Oliver Trace:[00:12:24] Yes, do both.

Iain McGilchrist:[00:12:25] Another brilliant piece of research, not by Lourenco, but by a chap called Vadim Degelin and an Anglo-american colleague, Marcel Kinsbourne. They did a fantastic experiment in which, similarly one hemisphere at a time was disabled. Instead of asking them to draw a picture, they asked them to respond to a syllogism. Is it true or is it not? Now syllogism, to remind you, is a couple of propositions which, if true, lead to a conclusion, and the classic instance that is always given in philosophy seminars is: all men are mortal, Socrates is a man, Socrates is mortal. Fine. But these particular syllogisms that were given to these patients had a twist to them, which was that one of the premises was true and one of them was false. So, for example, all monkeys climb trees. True. The porcupine is a monkey. No. The porcupine climbs trees. Now, I have to explain that annoyingly enough, there are porcupines that climb trees. But let us assume for the purposes of this, because it wasn't known to the experimenters or their Russian subjects that porcupines climb trees. So they were asked the conclusion, so does the porcupine climb trees? And they were asked this in three sets of circumstances. One was in the normal intact state. The second was just with the right hemisphere, and the third was just with the left hemisphere.

Iain McGilchrist:[00:14:04] And what they found was a very consistent pattern that is quite astonishing. So the same person, these are not just aggregated data, but the same person when asked, is it true? Says, no, it's not true, because of course the porcupine isn't a monkey, so it doesn't follow. The right hemisphere, as far as the same question, says broadly the same thing, but a little bit more emphatically: it's wrong here, it can't be right. The left hemisphere on its own answers: it's true. The examiner says, but why is it true? Don't you know a porcupine is not a monkey? And they say, yes. And they said, well, so it's not true, is it? Well, it is true because the porcupine is a monkey. But you do know a porcupine is not a monkey. And the person replies, yes, but that's what's written on this sheet of paper. So what the left hemisphere is interested in is the internal consistency of an entirely theoretical construct. If it follows according to the logic, it is true, whereas the right hemisphere and the normal intact person balancing these things is making judgments about reality on the basis of experience. So, one thinks this is very unusual…

Oliver Trace:[00:15:23] I should add that it is popularized in culture by the saying computer says no, which is a line in Little Britain.

Iain McGilchrist:[00:15:31] Yes, it's absolutely brilliant. 

Oliver Trace:[00:15:39] Well, it is perfect. But do go on.

Iain McGilchrist:[00:15:42] Especially the obstetric admission, I think is completely brilliant. My take on it is that we are we are taking this attitude more and more towards reality, that if the box is ticked, then it happened. And if the box is not ticked, it didn't. If it fits into the category, it's real. If it doesn't fit into the category, it's just not real because the computer can't compute. But I have a correspondence with an American woman who's a doctor and a librarian, and she told me this story. A friend of hers got a message saying, come quickly to the hospital. Your brother has died in a mining accident. So she went to the hospital and she was taken to the morgue. And they took her to the freezer, and they opened the drawer. And there lay her brother, and it was her brother. And she bent to kiss him. And in doing so she thought, this is a little bit strange. He's slightly warm for someone who's been in the freezer. And she felt his hand, and she thought, that's also very odd, and I think I can feel just a very slow pulse. You know, I wonder if he's really dead. And so she went to the nurse who was standing by and who had a clipboard with her and said, I just wonder if my brother could be alive. To which the nurse replied with the immortal words, now don't you worry about that, dear. It says quite clearly on this piece of paper that he's dead. The friend then ran out into the corridor and grabbed a passing medic who came in and administered Intracardiac adrenaline. And the brother survived.

Oliver Trace:[00:17:38] Shocking, really.

Iain McGilchrist:[00:17:39] Actually, I went back to look at the email the other day, and she actually says the nurse went over and felt the body and agreed that it was rather warm, but said, don't you worry about that, my dear. It says on this piece of paper.

Oliver Trace:[00:17:49] It is shocking and I think we all feel it also, where not only are people relying on what's in the box, but trying to put life into the box.

Iain McGilchrist:[00:18:00] Certainly.