Monday, December 05, 2005

Interface between the two ‘cultures’ is the human brain

Dr. V.S. Ramachandran, Professor at the University of California talks to The Indian Express Editor-in-Chief Shekhar Gupta on NDTV 24x7’s Walk the Talk programme about his path-breaking research into the human brain and the human mind. The Indian Express September 20, 2005

If you go back to ancient Indian philosophy, people talk about aham Brahma asmi and all of that. But now we can actually get to the physical basis of consciousness, self-awareness, what it means to be human. Ultimately all your joys, your sorrows, your hopes, your fears, your ambition, even what you think of as your own private self, is basically just the neurochemical activity of those one hundred billion little wisps of jelly in your head which we call neurons. That’s what it all is, that’s what reality is — the activity of neurons. It’s amazing that we know so little about the brain. If there’s something wrong with your thinking, even a trained neurologist will say you’ve got dementia. All the activities of thought are encompassed in one word: ‘dementia’. This can’t be right. Surely there are dozens and dozens of types, styles, of thinking, and many areas of the brain involved. What’s exciting for us is that we can begin now to approach these questions empirically: What do you mean by willing an action? What do you mean by ‘self’? What do you mean by seeing red? You can begin to answer all of these questions by looking at the physical structure of the brain.
If you close your eyes, you have a very vivid image of your body parts—it’s called your body image. When you amputate somebody’s arm, the astonishing thing is that even after the operation the patient continues to vividly feel the presence of that arm. He himself is very surprised by this—he’s not stupid, he knows that his arm has been amputated. But he says, You’ve removed the arm, I don’t see an arm, but I vividly feel my fingers, my wrist, my elbow. This is called a phantom arm. It’s important clinically because many people feel excruciating pain in this phantom arm. Chronic pain in a real arm is hard enough to treat; how do you treat a patient who has pain in a non-existent arm? It turns out that there’s a complete map of the body surface on the surface of the brain. When you amputate a person’s arm, a gap remains, corresponding to the hand, but which doesn’t receive any signals. Instead, the signals from the face invade that territory. It shows that there’s a great deal of malleability of connections in the brain—what we call plasticity. People didn’t realise it before we’d done that. That was the breakthrough.
When you amputate the arm and you touch the patient’s face, the patient says, Oh, you’re touching my fingers. It’s a very simple clinical observation, but we said that the reason this happens is because the signal is now going to the wrong part of the brain. There’s been a cross-wiring, and it’s now invaded the vacated territory corresponding to the missing arm. This happens astonishingly fast, in clinical terms. In a couple of weeks, the face skin starts sending its sensory input to a new brain area. It’s radical because it shows that brain maps can change over distances of seven centimetres, even in the adult brain, challenging the clinical dogma that new connections cannot form in the adult brain. It suggests that the brain has a tremendous amount of malleability or plasticity. What we’ve shown is that if you put a mirror in front of a patient, and he looks at the reflection of his normal hand, you resurrect his phantom, it’s as though his arm has come back. The amazing thing is that if he now moves his real hand, he sees the mirror reflection moving and he feels like the phantom is moving. This in many cases seems to relieve the painful cramping sensation in the phantom arm.
But, you know, people think Nazism was some isolated, perverse phenomenon. But it’s not an isolated phenomenon. You see it time and again in human history. Few people know that Nazism originated in the US. It was begun in Cold Spring Harbour by two men named Davenport and Gooder. They said that immigrants from Europe were mentally subnormal; that Jews should be sterilised; imbeciles, epileptics, homosexuals should be sterilised; alcoholics should be sterilised because alcoholism runs in families. This was all said in America, just two decades before Nazism. Hitler took these ideas to absurd limits. But even within America, eugenics became a very popular idea. Thank God, it wasn’t successful—think of all those Jewish immigrants who came to the US and made such astonishing discoveries in science. In fact the ratio of Jewish to non-Jewish Nobel Prize winners is something like twenty to one, while Jews are something like five per cent of the population. So there’s two hundred times more of a chance of getting a Nobel if you’re Jewish—not that I believe in genetic differences. Absolutely. Our own caste system is not different from what Davenport was doing in the US and it’s not different from any other type of racial discrimination.
Well, actually, we can go further. If you look at the evolution of ideas, the evolution of culture, among humans, you will find a tremendous upheaval of intellectual activity always occurring when things come together. We have to celebrate our diversity of cultures, not homogenise them, or marginalise a certain group. This is one thing that I’m afraid of with regard to the corporate homogenisation of the entire world, the Disneyfication of the world. I dread seeing a time when the world consists entirely of homogenised Nike shoes and McDonald’s fast food. What we call India or Indonesia, or culture or civilisation, will just be relegated to the status of little museums. Most of my work is characterised by building bridges—dissolving the barrier between what C. P. Snow called the two cultures: arts and humanities on the one hand and the sciences on the other and, he says, never the twain shall meet. I’m disputing that. I’m saying no. I’m saying the interface between the two ‘cultures’ is the human brain.
One of the things we have found is that there is a curious condition called synaesthesia. Normally, our senses are separate—touch, hearing, taste, smell and all that. Synaesthetes are people who are otherwise completely normal, but they get their senses muddled up. So they’ll say, Five is red; every time I see a five, I see red. Every time I hear sa, it’s blue, re is green, ga is purple—every tone has a colour. People used to think they were crazy and just dismiss them. We went in there and figured out what’s going on the brain. First of all, we’re sure they are not crazy. These people really see the colour when they see the number.
That’s correct—in some senses they are more gifted than us, you could put it that way. We found that there are specific areas in the normal brain which handle colour and number. In the normal brain, they are quite distinct. In these people, they get mixed up, there’s a cross-wiring caused by a genetic flaw—or, no, I wouldn’t call it a flaw—a genetic change, a gene mutation that causes excessive cross-wiring in the brain. Now, if this cross-wiring occurs everywhere in the brain, you get a greater propensity to link things. That is the basis of creativity and metaphor. So here you’ve started with this quirk, synaesthesia; from there you can go to the genes, you can go the brain areas, and maybe these can help us understand what made Shakespeare or Tagore creative.
I have nothing against it. A lot of Western neurologists, neuroscientists, debunk it, say this is all just Eastern fringe science. But Eastern science has always approached the world, including your own internal world, the mental world, from the inside, through introspective experiment. Western science is purely empirical, looking at it from the point of view of a detached external observer. All of Western science, indeed all of science, is based on the rejection of the subjective—saying there is no red, there is no green, there are only long and medium wavelengths. For all of Eastern philosophy, the starting point is you—although in the end they say this ‘you’ also doesn’t exist; it’s part of the supreme reality. There’s no tradition of experiment in the East. Even in the West, there isn’t a tradition of it—Aristotle did not understand experiment, the Greeks didn’t understand it. It’s only when Galileo came along in Italy that you define the birth of experiment.
He said, What else is there—it recalls the sentiment of Jung who said the same thing. What I would say is that words like ‘God’ or ‘spirituality’ are used very loosely—they mean different things to different people. If you talk about God in a very personal sense—there’s an old man there, watching you and punishing you for bad deeds—that’s probably just mumbo jumbo. On the other hand, if you’re talking about God in some very lofty, spiritual sense, as being the deeper truth underlying all appearances, no scientist can dispute that. You can say, I don’t know; so, you’re agnostic. I would classify myself as an agnostic, like most of my fellow scientists. There’s no evidence to say there is no god—I think that’s a silly position. Equally, there is no evidence to say there’s an old man sitting up there and watching you.
No. Not the existence or lack of existence of God. But we can probe more deeply into what makes people religious. We find, for example, that people who have epileptic seizures originating in the temporal lobes, have very strong religious sentiments. They say, I experience God. So we know that neural pathways in the temporal lobes are somehow involved in religious belief in God—but that doesn’t negate the experience. We’re not saying that because religious belief originates in the brain, there is no God—obviously not.

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