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Susan A. Greenfield

Susan A. Greenfield

Susan A. Greenfield is a leading neuroscientist and professor based at the Laboratory of Physiology and Pharmacology, Oxford. She is the author of Mindwaves, Journey to the Centres of the Mind, The Human Brain: A Guided Tour and The Private Life of the Brain. In 2000 she was awarded a CBE, and in the first list of its kind, announced on 26 April 2001, was made a people's peer.

What does the term ‘science’ mean to you?
To me science means a way of looking at the world. It's not so much a noun but more a verb, it's a way of doing something. If you approach the world and try to understand it scientifically, you have an idea and then you test that out idea with an experiment, and then you refine or redefine your view and then formulate another idea or hypothesis in the light of what you've found from the experiment. So, it's more scientific method than science. What excites me enormously about it, compared to philosophy, is that you can test. If you're wrong, then you have to abandon the idea, but it's very exhilarating because you really can find out the truth.

Historically, which scientific figures have meant the most to you?
Inevitably I'm drawn to famous women scientists, and there are very few of those. Rosalind Franklin, without whom Crick and Watson wouldn't have had the data for discovering the structure of DNA. Marie Curie who against all the odds won two Nobel Prizes. These women really are beacons, and I think what they stood for on the way they worked really is very inspirational.

Do you think certain barriers still exist to discourage girls from becoming involved in science?
At the junior levels it's not so much a problem, there are lots of girls doing science at university. The problem occurs when you want to become more senior. It's at that stage, in your late twenties or early thirties, that you might be considering starting a family. If you take time off and have a baby, you don't have a tenured job. If you don't have a permanent established university job, or a job in industry, when you try and go back you'll only be able to apply for a grant if you've got publications, and you won't have publications if you've taken time off. My own view is not to stop young women doing original science, but to lobby the government so they could ring-fence funds for pump-priming for women and girls that have had time off to have children; just to compete with each other, not with the world at large. Funds would enable them to get back on their feet scientifically. If we don't do that, they come back as technicians, or in somebody else's lab. For some that's very fulfilling, and might fit in with their domestic life, and I don't want to denigrate that, but if you really want to be a scientific leader then you'll need to run your own lab sooner or later and get your own grant. The alternative, and I find this unfortunate, is to wait until you do get a tenured position, until you get a lectureship or a good job in industry. By then you're probably in your mid-thirties and some women don't want to wait until their mid-thirties to have a child.

What one scientific development has changed our lives most profoundly?
If one had to nominate the most important scientific discovery, important in the sense that it had had most impact on people's lives, I suppose people would point to Crick and Watson and the structure of DNA. To stand back a bit and think of other things, the discovery of electro-magnetism by Michael Faraday at the Royal Institution has really changed everyone's lives, arguably even more than molecular biology has done. Again speaking as a woman, but also with a mind to men, I think another huge change in the sixties was the development of The Pill, which is now coming up to its 50th anniversary. The chemist Carl Djerassi was the first person to develop the structure of an oral contraception. If you think about it, that that really has changed the way people live their lives.

Are there any discoveries that would have been best left undiscovered?
I honestly can't think of anything. You think of plutonium, or you think of the development of the atom bomb. Obviously that was put to evil use, but by the same token, it's been put to good use as well. That's the thing about science, it's not as if it is intrinsically an evil finding, it's more that it can be abused. I think our job nowadays as scientists is to share with the public what the science actually means, to have a truly scientifically literate society so that, all together, we can evaluate a particular technique or discovery and make sure that we harness it for good and minimise the ill that comes from it.

Is science amoral? Or, are there always moral implications for scientists and their discoveries?
In once sense it is amoral, it is neutral. In itself it is just telling you something about the way the world works, in that sense it's a discovery as opposed to an invention. It's not a technology as such, it's finding out about something that exists. How that discovery is harnessed can be used for good and ill. I think for everything in science one can think of abuses and uses of both those things.

What do you feel to be the problem of consciousness?
For me, it is what has been referred to as 'the hard problem' it is like the water into wine issue. How does the sludgy, physical brain, that can be objectively studied, held in one's hands, and shared with other people, how can this objective entity be responsible for generating a subjective sensation. You have access to the feel of the sun on your face as it seems to you, the taste of the wine on your tongue as it seems to you. How is the water of the bump and grind of boring old brain cells somehow translated into this special wine of consciousness, of first-hand experience, that's the real problem.

As a neuroscientist, what would you say about emotions?
What can a neuroscientist bring to the party? I feel very indebted to philosophers, because what they have made us aware of is the quintessential subjectivity of consciousness. Many scientists have ignored that subjective element. They've just documented unusual features in the brain, said consciousness is unusual and said that the one might cause the other. I don't think that's good enough. I think we have to do what scientists don't like doing and take on board this subjective element. We don't like it because as scientists, of course. We are bred to be ruthlessly objective. I think this poses difficulties for the emotions, because the whole point about a feeling is that you are feeling it. It is your emotion, it is not my emotion. You can tell me you're in love or you feel happy or you feel sad but I can't share that emotion with you directly. You might convey it to me if you're artistic or poetic or articulate, or if we're close to each other, but I can't actually share it with you and I think that is the real problem. Studying emotions, unlike learning your memory, is touching on the absolute feel of consciousness and that's why I say that emotions are the building block of consciousness.

Would it ever be possible, or desirable, to reduce emotion to a physical level?
I would answer, of course, that everything is physical, I don’t think it's beamed in from planet Zog. I think that every emotion every feeling every thought we have is somehow rooted in the physical brain and therefore it's physical. Underlying it is some slight shift of molecules, a slight cloud of transmitters being moved around, some small bit of brain cell that's either atrophied or retracted or expanded. Something is happening there that is accompanying that subjective sensation. As scientists what we can do is look at the co-relations, look at what is matching up with a particular emotion. That's not to say we are reducing it to any particular component. I take exception to people that say that an emotion is locked inside a particular chemical messenger or transmitter. I feel very uncomfortable if I hear people talk about the 'transmitter for happiness' or for depression and so on. Just as I feel the gene for this or the gene for that is inappropriate, or even the brain region for such and such an emotion, fear for example. That to me is logically flawed and conceptually misleading. I think we have to see the whole brain working together using all its chemical, anatomical and physiological features. That's what I try and set out in the book, I don’t make any claims for explaining how one causes the other, how the water goes into wine, but I do venture a testable idea for how one might co-relate what you're feeling with what is literally happening in the physical brain.

Do you think it will ever be possible to replicate consciousness?
Perhaps one scientific way of doing it would be to build a machine that was perfect in modelling consciousness. The problem with models is this; a model is something that captures the quintessential feature of the thing that you are studying and it does away with the things that you don't need. Usually it's less elaborate than the real thing but it captures the absolute element of whatever it is you're interested in. With consciousness we cannot know what it is we can leave out, what we can strip away. We don't know what the minimum kit is. If you have to keep everything in then you don’t have a model because the whole point of a model is you've left things out. If you keep everything in then by definition you have the thing itself. So, the only way you can be sure is to have absolutely every element of the human body and the human brain present, and the only way to do that takes about nine months usually!

Given your understanding of consciousness, is there a place for God or the soul?
My own view is that we could define soul as a distinct entity from mind and consciousness and I'll say how I think this can be done. The mind, I argue in the book, is the personalisation of the brain through all the personalised brain cell connections that reflect your personal experiences as you grow. So, even if you're a clone, let's say even if you're an identical twin, you will have a unique configuration of brain cell connections. It’s this personalisation of the physical brain that I call the mind, because whenever we use the term 'mind' or refer to it we are thinking of personal views of things. I don't mind, he's broad-minded, narrow-minded and so forth; that's mind and brain. I think consciousness is different from that because you can lose your mind, you can blow your mind, you can let yourself go, but still of course be conscious. I think that this is what happens when people are on drugs or at raves or indulging in the traditional pursuits of wine women and song, drugs and sex and rock and roll. Now what about the soul then, if we've distinguished consciousness mind and brain, where does soul come in? Well, the one thing about a soul, the concept of a soul, whether you believe in it or not, is that it's immortal. Now if it's immortal, then it can't have much to do with the physical brain, because that for sure is not immortal. My own view is to say to people ‘look if you believe in the soul I respect that view, but I cannot see how it has anything to do with the physical brain or indeed the mind and that's what I know about. It's fine if you believe in it, it's fine if you don't believe in it, but it has nothing to do with neuroscience, it has nothing to do with the study of the mind and consciousness.’

Are there any philosophical implications arising from your work?
In the past the disciplines were very separate, the word 'neuroscience' wasn't even in very common use. People spoke about physiologists or anatomists or biochemists or indeed psychologists, and they spoke in a completely separate breath spoke about philosophers. At the turn of this century we’re seeing a merging of these disciplines. To understand consciousness we need to take on board the views of computer scientists, mathematicians as well as philosophers, neuroscientists and psychologists. I think that psychologists and neuroscientists are entering the party that was previously exclusive to philosophers and I think that we can actually help them. I'm not saying that we can take the territory away from them, or we can solve things they cannot solve, but because we are empirically based we can actually say whether something is true or if it's not true. I think that's very valuable because otherwise they'll never to be able to test out ideas. What they bring to the party is to emphasise the absolute importance of subjectivity which the scientists of course will normally, given half the chance, try and airbrush out.

Do investigation into brains and consciousness have any implication for a moral understanding of ourselves?
This of course touches on issues like free will and human accountability and I think one day perhaps Penguin will commission a book, which I find very exciting, on the frontiers between neuroscience and the law. The Bulger killers for example, were they responsible for what they did? If they weren't, why not? When would they become responsible? There's not a magic rubicon, even though the law might hold that above a certain age you're accountable. In biological and brain terms there's no sudden line that you cross when your brain has changed and suddenly you're working in a different type of way. Now we have people actually using as mitigating circumstances the gene for this and the gene for that, again one has to really re-examine the role of genes and determinism in the sort of person you are. Imagine the horror of shouts that would go up if I was to say ‘Hitler had the wrong set of genes and because it had this factor happen in his environment and that factor then we can explain it, and because we can explain it, it wasn't his fault’. I certainly would say, it was Hitler's fault that he did that. But why should we say for some people it's their fault they are accountable, for others it's their genes or it's their environment, why should we have discrimination of some people being excused and others not? And then even within a person, the fact that they can sometimes use, as they can in France, mitigating circumstances, like being out of their mind with road rage, or crime passionale? Why should you be in some state not accessing your networks and so on so that you're a responsible human being but you're like a small baby again? These are issues I don’t have easy answers to but I think we should have some guidelines and it does raise very interesting questions, not least that of free will.

Is there a difference between human consciousness and animal consciousness?
In the old days, people didn't think that animals were conscious at all an I think that that arises from the confusion of consciousness, the subjective sensation that you're feeling. Self-consciousness is an add-on, when you're a very small baby you're not self-conscious, I don’t believe a rat is self-conscious it doesn't look at itself in a mirror and think, I'm a rat. I would argue that primates probably aren't self-conscious in the same way that we are, but self-consciousness has nothing to do with this real big question of the subjective sensation of raw consciousness, what other people have referred to as core consciousness, for me it's the basic building block. I think anything that has a brain, however primitive, is capable of having consciousness. This is where I part company with people like Jerry Edelman, who draws a very clear line below which are creatures like the lobster, who he thinks are automata, and above, which he thinks are conscious. I'm very unhappy with that because in biology there is no clear demarcation within the animal kingdom of certain nervous systems from others. I'm very unhappy about suddenly saying the light switch goes on and suddenly some animals are conscious, some are not. I think that's a very unsatisfactory intellectual stance to take. I think the riddle can be solved more readily by saying ‘what if consciousness grew as brains grew?’ This would provide a happier way of looking at things because anything that had the simplest multicellular organism would have a tiny amount of consciousness, but consciousness would come in degrees and grow as brains grow. I find this a very useful concept in that it explains several things. it explains why we refer to a raised consciousness or a deepened consciousness or a blunted consciousness. It suggests that at different times from one day to the next in our lives we have different degrees of consciousness. I think that also has an impact on foetal consciousness and the foetus being conscious, which I believe it is, simply because the alternative is completely potty. The idea that a baby only becomes conscious after birth I find very odd.

Do you think there are aspects of ourselves which are essentially unknowable?
That's a kind of Catch-22 because if it's un-knowable you won't know you've got them so I suppose the obvious answer would be yes, because I'd never be able to test it and that's why it's a philosopher's question rather than a scientist's one. It's not very helpful to a scientist because if you can't test it and you can't know it then what is the point even of positing the question. Having said that I suppose the science equivalent or the nearest to it would be talking about the sub-conscious where you're not aware of the reason for a certain action or a certain view or a certain attitude, but nonetheless it's there. For me the sub-conscious can be actually have its roots in the connections between brain cells that mirror your experiences in life, that represent groups too small to be enough to impact on your brain and determine the size of your consciousness.

How important is it to bring science out of the labs and make scientific understanding public?
I think it's very important to bring science out of the labs. One of the things I firmly believe is important for this century is the democratisation of science along with the democratisation of knowledge in universities. I think it's very important that everyone is scientifically literate. If not, we're going to have a divided society where scientists are reviled as dysfunctional nerds, or ignored, or allowed to just do what they like. What we must have is a balanced society where everyone can contribute to the debate, and you can only contribute to the debate if you understand the basic ideas, the basic concepts. You don't have to be a card-carrying scientist but you have to not be scared by it and you have to be prepared to learn what the words mean, that's all.

What does your role as Director of The Royal Institution mean to you?
To be Director of the Royal Institution is a great honour. There’s a great distinguished line of predecessors behind me including Michael Faraday, Humphrey Davey, William and Lawrence Bragg, Lord George Porter, many of whom were Nobel Prize winners. It's a very exciting place, because as well as being the home of electro-magnetism and of molecular biology, it's also a place that for 200 years has been diffusing science for the common purposes of life. Long before people invented the phrase 'public understanding of science' we've been doing it at the Royal Institution, indeed it was the first one-way street in London because the lectures were so popular that the carriages were congested and therefore it was made into a one-way street. What I'm trying to do there is reinterpret that original vision of Michael Faraday for the 21st Century.

How did it feel being voted Observer Woman of the Year?
I thought they must have got it wrong, there were so many other women more deserving than me, but on the other hand I was very pleased because it sends out exactly the right signals. One wants to send out messages to schoolgirls, to other women, who are thinking science is just a male dominated profession. If I can send out signals that you don't have to be a man in a grey suit then I'll feel it's worthwhile.

Have you ever you thought of writing fiction?
There's one ambition I still have, and that would be to write a novel. I tried once and it sounded like the woodentops; I don't have the skills for developing character and dialogue. I've read some brilliant authors and it's depressing in a way because you think how will I ever write like that? Still, one can dream, and I suppose one day I'll dream of living in the South of France somewhere and sitting there like Somerset Maugham and writing novels.

What would you most like to be remembered for?
I have three ambitions in life. One is to really make The Royal Institution a centre where anyone interested in science can come both formally and informally and discuss the impact of science on society. I also want to develop a better treatment, not necessarily a cure, but a treatment for alzheimer's and parkinson's. And finally I'd like to feel I'd made a serious contribution to the debate on consciousness.

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