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Sam Wang is an associate professor, Department of Molecular Biology and the Princeton Neuroscience Institute.  Wang grew up in California and studied physics at the California Institute of Technology. Seeking[…]

A conversation with professor and neuroscientist.

Topic: Sam Wang on the 10% myth


Sam Wang: The 10% myth is a funny one because it doesn’t come from an identifiable neuroscientific discovery. The earliest mention of the idea that you only use 10% of your brain comes from the motivational speaker and writer Dale Carnegie in “How to Win Friends and Influence People.” Actually, Lowell Thomas said in the preface. And before that, the only statement that resembles that is again, as I mention before, this pioneer of psychology and as it turns out neuroscience, William James. He told audiences that we only meet a fraction of our full potential.

And I think that statement is true because it certainly the case, for instance, that IQ scores have gone up a few points per decade in modern times, which suggest that there’s some influence in the environment on what we can become.

In that sense, we maybe still exploring our full potential. But the 10% idea is literally not true. If you damage any part of the brain, you can… If any part of the brain is damage, it can lead to deficit as a function. For instance, if I damage… If a person experiences damage to the cerebellum, which guides smooth movements, then people are unable to move smoothly, unable to learn new things like a dance step or a tennis stroke. And you can come up with similar kinds of observations for all parts of the brain so you really need the whole thing.

You need a 100% of your brain. If any part of your brain went missing in action, you would notice and you’d be sorry. Well, depending… Actually, depending on the part of the brain, you might not be sorry.


Topic: Sam Wang on alcohol and the brain


Sam Wang: A really common belief about the brain that you hear at parties is the idea that drinking alcohol kills brain cells. People make light to this all the time. The truth is that alcohol can damage the brain but it’s highly unlikely to kill brain cells. When people look at the brains of alcoholics’ postmortem, it takes decades of drinking before loss of brain cells becomes apparent, okay? So… And in fact, loss of brain cells, when it does eventually happen, it’s associated with a profound loss of memory, a thing called Korsakoff’s syndrome. And that happens after decades of drinking. Now, having been said, alcohol does cause damage to the brain.

So one thing that has been observed is that heavy drinking for years does lead to shrinkage of the brain. And that is probably the source of the idea that alcohol kills brain cells that you can observe shrinkage of the brain.

Now, let’s put these two together. Alcohol causes shrinkage of the brain but the cells don’t diminish the number so what that suggest is there something about each individual cell that shrinking. And what’s believed is that the trees, the dendritic trees that neurons have, may retract a little bit and they’re constantly growing and shrinking. And so, what’s believed is that, perhaps, they retracted a little bit. And the practical implication of this is that if you stop drinking, then they, perhaps, will grow back. Okay. So that’s the practical implication.

And so, even though the idea is a myth, it’s still important to remember that drinking alcohol is not a good thing for your brain when you do it for many years at a time. I have more that I forgot to give so can I fill that in? Sorry about that. Okay. The other side of the coin is that moderate amounts of alcohol are not harmful and, in some cases, can even be helpful. And there’s a very specific case, which is red wine. It turns out that moderate amounts of red wine seem to have some kind of protective effect on brain function especially as you are getting older.

And it’s not known exactly why but there’s a general principle, which is that things that are good for your heart and your cardiovascular system are also good for your brain. And so, there are health benefits that have been demonstrated of red wine, some of which are mediated through the compound resveratrol. And what’s been observed is that up to 3 glasses of red wine per day for men and up to 2 glasses for women is either neutral or slightly beneficial for brain function. And that adds up to a bottle for a couple per day so that’s easy to remember.


Topic: Sam Wang on drugs and the brain


Sam Wang: All drugs exert their effects by acting on some kind of receptor on the brain. In many cases, that receptor is identified.

To pick an example, cocaine and methamphetamine act upon a molecule whose job it is to suck up dopamine back in to cells after it’s been released. And so, those are blockers of dopamine re-uptake. Another example is LSD, which acts upon very specific receptors for the neurotransmitter serotonin. So all of these acts upon different receptors to cause their effects to cause hallucinations or intoxication or feelings of confidence or what have you. And a consequence of that is that they’re addictive to different degrees. So, for instance, alcohol is addictive. Nicotine in cigarettes is addictive. Cocaine and methamphetamine are highly addictive. And so, those tend to lead to dependencies and bad effects that you feel for many years and you get trapped in using those things.

Other drugs seem to not have much addictive potential, and you mention LSD. LSD is not addictive so far as anyone can tell and does not seem to lead to long-term harmful effects. No, it does not. All these drugs act on different things. I mean, they’re not clean laboratory design experiments that we can perform in our brains. They tend to have lots and lots of different effects. I think that if alcohol were to appear as a new drug today, I think it would be basically banned immediately because of all the drugs that are available, it’s this nasty solvent that can kill cells, that can cause dendrites to shrink, that can lead to us to be unable to operate machinery safely, and can cause people to beat up their love ones and spouses, I mean, it’s a fairly serious drug. But it’s been around long as since though through familiarity, we think its okay. Wine, beer, liquor, whatever, it’s fine. And the flipside of that is something like, say, LSD, something that’s relatively recently come into use. And there’s no denying if you were to take LSD, you would need to be in a safe place and be important to put yourself in a position where you didn’t hurt anybody or hurt yourself.

There are not long-term damaging effects of LSD the way that they are for alcohol. And so, there’s this curious property of these drugs that sometimes are… perceptions of them as a society are not quite the same as the mechanisms of what they do to the brain. One drug that’s pretty unambiguously bad is cocaine methamphetamine. A rule of thumb seems to be that drugs that blocked dopamine uptake have a lot of potential for addiction. And that’s because addiction seems to work through dopamine pathways on the brain. And they lead to dependencies that can be very bad for you. So dopamine uptake blockers seem to be bad for the brain.


Topic: Sam Wang on book smarts vs. street smarts


Wang: I think Goleman’s ideas are very interesting. This old school idea that basically no one believes anymore, which is that intelligence is just described by one factor, a perimeter that people use to call G for general intelligence. And either you had more of it or you had lots of it. And a certain element of that is still true because there is a thing that you can measure on tests that has to do with fluid problem-solving that one… that people still call G. And so, that part’s true.

But I think one thing is interesting there, with Goleman, is the idea that there are many mental capacities that we have and they are, to a certain degree, independent with one another. Now, it turns out they are less independent than one might imagine. It turns out that on average, people who are better at, say, IQ tests on average tend to be better in social intelligence. Now, that might be hard to believe when you go to university and quiz your average mathematician. Not all those people are all that socially advanced. But nonetheless, there is a positive relationship among these things and they rely on slightly different brain systems. So I think it’s possible for these capacities to be somewhat independent of one another.


Question: What is a creative brain?


Sam Wang: Creativity is a pretty general concept. And in order to reduce it into something you can study, you have to start thinking about a problem that you can give somebody in the laboratory.

And so, for instance, there’s a kind of problem-solving called divergent thinking, finding solutions that other people do not find at the same problem. Okay. So, for instance, an example of creativity, an animal might be; if you have a crow; imagine a box in which the box can either be opened by flipping the lid like this or by pulling on the lid like this. And what ethologists have discovered is that when you take a crow, most crows will learn how to open the box like this and flip it like that. Okay.

And occasionally, a crow will have the innovative thought of pulling the box the other way. Okay. So that’s an example of divergent thinking that you can identify in a crow. And crows even have social learning.

So, for instance, if one raven sees another raven do this, then, in fact, it can learn to do the innovative way of solving the problem right away. And that’s an example of social learning. And this is clearly something that’s very highly developed in us, right? Our cultural evolution occurs far, far faster than biological evolution. And so, that kind of creativity of tool making is something that crows have a surprising amount of… that we have. And so, one question is how to study these things. And you have to cook up tasks that are more germane So, for instance, one example is left-handers.

On average, left-handers seem to be more prone to divergent thinking and creative ways of solving problems at least in the laboratory context. So that’s one example of a demographic that seems to have more of this, whatever it is.


Topic: Sam Wang on left brain vs. right brain


Sam Wang: So the popular belief about the left brain and the right brain… And people are usually talking about the cerebral cortex when they talk about these things is that the left half of the brain is rational and problem solving and uncreative. And somehow, the right brain is creative. It can help you draw better, right? Now, the truth is more complicated. Because, in fact, the hemispheres of the brain… Because the hemispheres of the brain are heavily interconnected by the structure, that’s… basically, this dense band of fibers called the corpus callosum.

And what seems to be really the case is the left half of the brain is important for mathematical reasoning, for generating language, but it’s also a storyteller. So, for instance, in split brain patients who have their corpus callosum cut, when you show a picture and you play a picture association with the right half of the brain by showing the left half of the world… of the person’s world things and ask the right half of the brain to do something, the right half of the brain will happily play picture association. Then, if you ask the person, why did you make that association, the left half of the brain makes up a story.

So, for instance, you could show the right half of the brain a snow scene and a chicken claw and the left brain sees the chicken claw, the right brain sees the snow scene and then you ask the right brain what goes with it, and the right brain will pick a shovel. And then, you ask the left brain, why did you pick a shovel, and the left brain saw the chicken claw and the left brain makes up this crazy story. The left brain will say, well the chicken lives; that’s a claw, it goes with the chicken, the chicken lives in a coop, you need a shovel to shovel out the chicken coop. And it’s this totally made-up story. And so, it turns out that the left half of the brain is perfectly capable of making up stories. And so, that seems to be; that sort of creative, right? That doesn’t fit the stereotype.

I think what’s more the case is that the right brain is important for certain things. So, for instance, the left brain produces language, the right brain produces porosity, which is the emotional content of a language. In many ways, the right brain, on the other hand, is quite concrete. And so, I think the story is more complicated. And I think these cultural ideas about left brain, right brain have basically blown up all out of proportion to what scientists have actually found about the left and right brain.


Question: Are all brains created equal?


Sam Wang: The question of nature and nurture is; I wouldn’t call it settled, but I will put it like this, we are all born with the genetic inheritance and that genetic inheritance sets boundaries on what we might become. They guide us in the sense of establishing about one quarter of the variation of what we might become and that, when it comes to intelligence or personality, it’s some minority of what we could become.

And then, against that genetic background, then our genetics and environment, the experiences that we have and the nutrition that we get interact with one another and that been shapes us over the course of childhood and a lifetime.

So most of the variation turns out to be believed to be environmentally induced or based on experience and so some interplay between the two that makes us who we are.


Question: How do brains develop?


Sam Wang: One thing that’s interesting about child development is that so much of it… There’re so many changes that take place in children’s brains, not only from birth to the age of 6, ‘cause this when people think of brain change, but also even through childhood into adolescence. So one thing that probably does not help is passive experiences for the child.

In the classic example, this is the Mozart myth. The idea that playing Mozart or the classical music to a baby will make the child smarter. What seems to be important is active engagement. So, for instance, learning to play a musical instrument is associated with improved spatial reasoning. And that seems to be something that really helps a lot. Another thing that helps is talking to children. It’s been shown that there’s a positive relationship between the number of words the child hears per day and IQ scores.

And this is true even when you crook for social economic status. And so, just simply speaking to a child, playing with her, talking with her, that kind of cognitive stimulation seems to have a lasting positive effect on the child’s development. And that’s something that I think any parent can and should do.


Question: Is genius overhyped?


Sam Wang: Well, it certainly the case that some people who are called geniuses have the ability to link unconnected ideas and ways that other people can’t see. But one important factor that sort of, I would call that isn’t so romantic, is this idea that Gladwell talks about, which is just the hard work of having all that information on hand and developing expertise to thousands and thousands of hours of practice.

We talked earlier about Google making us dumber. Well, look, if Google removes the need for us to have all that knowledge on hand, then that removes from us the ability to have these facts in our heads on hand. And so, I think that this is one area where we can think about something that maybe gets lost a little bit, right? Geniuses are people who, in many cases, are people who have a lot of information directly at their beck and call and they think about it and they start putting it together. So, one component of genius is sticking together things in unexpected ways.

But another component is having those things to stick together, right? And I think that there’s an element of truth to this idea of thousands of hours of practice, making a creative scientist or artist or writer or whatever it is that we may care to call a genius.


Question: What environments are most conducive to learning?


Sam Wang: So one thing I’ve experienced at Princeton is that public spaces where my colleagues and I are likely to cross paths are excellent places to share ideas and to have discussions that rise up spontaneously. And at our campus, the Genomics Institute is a newish building that has an atrium where we run across one another, we have lunch or coffee or what have you. And that seems to be a place where there’s a lot of ferment both socially and also intellectually. I repeatedly have meetings there. And so, I think one principle that comes up in modern design, for instance, in scientific buildings is creating spaces where people can cross paths.

And I think that’s an incredibly important aspect of creating of spaces where creativity is fostered. And it’s a real live version of Facebook or Google. And as much as people like to talk about those social networking sites, personal networking between live people, face-to-face, is still far more effective than any kind of online interaction.


Question: What is neuroplasticity?


Sam Wang: Well, people have known that experience can change the brain ever since it became known that the brain was the seat of consciousness, thought, and experience. And so, I would say that for hundreds of years, it’s been known implicitly that the brain must undergo change because, of course, if the brain is the physical object by which we generate our consciousness and ourselves, then there must be some physical change happening in the brain.

So in that sense, I think neuroplasticity has been known implicitly for centuries. But I think it’s really been in the last few decades become really appreciated exactly what happens in the brain. So about a little over 50 years ago, a Canadian psychologist named Donald Hebb suggested the specific idea that experience could change the brain in ways that perhaps there’ll be some pathway that gets activated in an order of events that gets turned on when we experience something and then, when we recall it, we are, perhaps, playing it back, and have suggested that. Before him, the pioneering psychologist William James suggested it.

And you can even find the suggestions of this in writings of Thomas Hobbes and even Aristotle. So it’s been in the last 50 years or so that this suggestion that’s been around for a millennia has turned into a very concrete suggestion about neural pathways. So that’s neuroplasticity in the adult brain. Then, there’s also neuroplasticity in response to injury and also during development. And all these things are facets that have been studied facets of neuroscience that have been studied over the last few decades and it’s becoming really appreciated how much the brain can change.


Question: Is stress good for the brain?


Sam Wang: Well, certainly… When challenged, we can do more and everyone knows this. In the absence of challenges, we don’t necessarily reach our full potential. Now, I don’t know that that necessarily means that stress per se is good for the brain. What I mean by stress is very specifically secretion of steroid hormones. These hormones that turn up when we are under some low-level pressure, when we’re not allowed to sleep or when we’re under some kind of bodily stress where we are put into some kind of adverse condition for long periods of time.

Certainly, pressure can make us perform better but chronic stress… It has been demonstrated to slow down the birth of new neurons, to reduce the plasticity of dendrites. And so, there are physical consequences of chronic exposure to stress hormones. And those long-term effects of stress are mostly unlikely to be very good for us.


Question: Does brain food work?


Sam Wang: I have, on my desk, a bottle of pills that I picked in China Town once, that are called brain enhancer pills. And I keep that sort of thing around, sometimes, my office as basically a joke. A lot of these supplements have no demonstrated positive effects on brain function. And that includes ginkgo biloba and includes other supplements that you can take. That’s one problem. Another problem, of course, is these supplements aren’t controlled for what’s in them.

And so, as a result, if you buy something like, let’s say, St. John’s Wort, there’s tremendous variation in what you’re getting when you buy those things. So even the claimed pharmacological agent that’s in them maybe present in highly variable quantities. And it’s something that we would never accept in some FDA approved drug.

The rule of thumb for foods that maybe good for the brain is that things that are good for your heart are good for your brain. So it’s, again, this principle of good for your heart, good for your brain. And examples of that include green, leafy vegetables. They include not having too much in a way of saturated fats because that improves your circulation when you get older.

And your brain lives off of oxygen in the blood and so you need blood. And so, when your heart is not getting the oxygen, your brain is not getting the oxygen. One category of foods that seem to be somewhat helpful is antioxidants. So, for instance, blueberries, especially wild blueberries, have antioxidant properties and they seem to have some kind of protective effect, cognitive function as we get older.

There is evidence that omega-3 fatty acids are good for both the heart and for the brain. And, in fact, I, myself, take omega-3 fatty acids. Of all these things, you can take. Just to put into perspective, the only things that I make a point of eating are those and blueberries. I like blueberries.


Question: Does art therapy work?


Sam Wang: Well, I’ll be honest. I don’t really know a lot about demonstrated effects of these therapies like art therapy and music therapy on the brain. I think one major mechanism that is worth thinking about is the idea that these therapies reduce stress. One thing that has been demonstrated is that stress hormones are bad for the brain.

So, for instance, sleep deprivation leads to the secretion of stress hormones, being in danger. Stress hormones arouse and the stress response arouse evolutionarily to be something that works briefly. If there’s danger or if there’s something that’s caught your attention and you need to get away from it, the idea is that your certain systems in your body shut down like your immune response. And the idea is that you got to shut down the unnecessary things so you can get away from danger quickly. So that’s the normal biological evolutionary history of stress hormones. But now, on modern times, we have situations in which stress is always present.

And so, one major way that these therapies may work is by simply reducing the secretion of stress hormones, which is good for the brain. Stress hormones, when chronically present, can damage the brain.


Question: Does physical exercise improve the brain?


Sam Wang: It’s not fully understood what it is that exercise does that’s good for the brain. The empirical observation is that the… one of the best things you can do to keep your brain alive and healthy is fitness training, things that get your heart rate up, the kinds of things you hear about, getting on the treadmill for 3 times a week for at least 20 minutes in each session. That’s a classic way of getting fitness training. And that’s been demonstrated to improve brain function especially in older people. The mechanism is not known.

Here are the two major candidates.

One candidate is simply improving blood flow to the brain. And, again, it’s back to the heart-brain principle, things that are good for your heart are good for the brain.

Another major mechanism that’s been suggested is the secretion of a signaling molecule whose job it is to allow dendrites to grow and to be plastic. And this gets back to what we were talking about before, about neuroplasticity. This molecule is called brain-derived neurotrophic factor. And if you know what a neurotrophic factor, you know from the name what this does. It’s a factor that’s made in the brain that causes neurons to grow. It’s a trophic factor. And that factor has been demonstrated to improve plasticity in dendrites. And one hypothesis that people are investigating is the idea that exercise; by triggering the secretion of BDNF, this neurotrophic factor, may lead to increase plasticity and improve brain function.


Question: Will sex drugs change the brain?


Wang: Well, that’s an interesting question. Because existing drugs like the ones that you mentioned are all about the plumbing and the mechanics of--especially in men of sexual performance. Something that cuts to the heart of who we are as loving or sexual beings is the feeling of love. And that’s a whole other category.

And major singling molecules in this category are molecules such as oxytocin and argenin-vasopressin. Oxytocin and vasopressin are secreted when we feel feelings of romantic love. They’re also secreted when we feel feelings of love towards a child. So, for instance, mothers, when they hear their baby cry, will feel their milk drop and the mechanism of that is the secretion of these molecules to cause milk to be secreted.

And so, it’s possible to reproduce feelings like that. Those same singling molecules are also important in generating a feeling of trust. So, for instance, people who take oxytocin in the form of a nasal spray exert more… express more trust when playing some negotiating game with somebody. And so, now, we’re talking about molecules that can affect our emotional responses to other people. And that seems to cut somewhere to the heart of what it means to be loving or sexual.


Question: How effective is meditation?


Sam Wang: Well, there’s a subjective report that meditators [report], right, feelings of peace, being able to focus.

There are many versions of meditation. And the version meditation people practice leads to different affects. So, for instance, Buddhists report a particular state of objectless compassion, so feeling compassion without any specific object, without a person as the target. One thing that’s been observed experimentally is that when you put people into a brain scanner and look to see what happens in their brains, it’s possible to measure a very large electrical oscillations in the brains of, say, Carmelite nuns experiencing mystical union with God or experienced Buddhist practitioners entering this objectless compassion state. And what’s observed is that you can see these oscillations, which basically are the result of neurons being active and synch with one another and being active more or less in cycle with one another.

Buddhist monks can achieve an oscillation of that in what’s called the gamma frequency bound that’s only found in non-expert meditators when they’re having seizures. Okay. So these people can do something extreme with their brains.

And I’m not sure that it reveals anything about the nature of reaching enlightenment or the benefits of meditation but, I think, one thing is very interesting about it is finding a neural signature that shows exactly which parts of the brain maybe trained when people learned to be very good at these things. And I think that, scientifically, that’s a rich source of questions for investigation.


Question: How resilient are brains?


Sam Wang: Well, our brain’s abilities to think about a modeled world are double-edged. More than any other animal, we have the capability, it seems, to look into the future and to make plans for the future. And that’s basically because we got those tremendous cortex, especially a prefrontal cortex, that allows us to make these plans for the future. But at the same time, we are also limited.

We are remarkably bad at seeing the downstream effects of what our acts will lead to 5 years or 10 years down the road. We’re just not very good at that. And so, it’s difficult to judge whether some life decision you make today will make you happy a few years down the road. One way to get around that is to simply find someone who was faced with the same decision a few years down the road, a few years in the past and ask them, well, how did you feel after making that decision. And so, one thing you can do is to find people who face with the same challenge and then they can report accurately how it made them happy or unhappy. One thing about happiness that’s funny is that we are remarkably resilient in adapting to that.

So you might imagine that something like losing a limb would really affect one’s happiness. But studies have shown that losing a limb; you’re less happy when you lose a limb but after a few years, you adapt that and it’s as if… almost as if you had not lost the limb in terms of your happiness. Some things never adapt.

Examples of things that never adapt out are losing a love one. If you lose your life partner, that makes you less happy and that doesn’t go away. Another thing that reduces your happiness in the long-term and never goes away is something that’s less serious, and it’s commuting. So it turns out that having a long commute makes you slightly less happy and you never get used to it.

Well, human beings are remarkably adaptable. Think of us as having come out of Africa, from this little valley, and then dispersing throughout the world and living in places like Finland and in Indonesia and the United States and all over the world.

It’s amazing how adaptable human beings are. And so, one thing that seems to be a very striking characteristic of humans including their brains is the adaptability, both by being clever and making tools and shaping our environments to be more satisfactory to us and also, adaptability in how we react to our environment. And so, one thing that seems to be a hallmark of our species is how good we are at that. And if you compare that with any other species, we seem to be very, very good. Our only close competitors might be cockroaches.


Question: When we science cure autism?


Sam Wang: Autism is been very much in the news lately and it’s pretty much everywhere you look. It’s been a really remarkable thing to watch, just as a phenomenon of watching people become very interested in it.

My younger sister is autistic. And when I was a child, the only thing I knew about autism was the fact that Karen was autistic. Now, it seems to be in the news everywhere. What’s known about autism… The number one thing that’s known about autism is that it seems to be largely genetically determined. If one identical twin is autistic, then the odds of the other twin having some kind of autism spectrum disorder is between 50% and 80%. And that’s just a tremendous probability. And that’s not the case for non-identical twins, for fraternal twins.

And so, that’s a major piece of evidence that autism is largely genetic. And one big story in the last 5 years has been the identification of genes that increase the risk of autism. And it’s not one gene, it seems to be some more complex polygenic disorder where you get dealt a bunch of genes from your mother and from your father.

And if you draw the wrong combination of genes, say, between 2 and 10 genes, then that increases the risk of being autistic. So that’s the main thing that’s known. As far as the later development of it, people are starting to look at structural differences between the brains of autistic people and what are called neurotypical people, and those are changes that take place in the neocortex, which is the largest part of our brain, and also the cerebellum, which people use to think of as being a sensory or a motor structure but seems to be, perhaps, important also for more advanced cognitive tasks. And so, the cerebellum has been [IB] in the last few years.

As far as treatments for autism, right now the one kind of treatment that seems to be somewhat helpful is behavioral therapy, especially when children are diagnosed and identified as needing the help young. And so, that is interesting because it’s the one way that seems to possibly help kids who have autism. And it maybe part of why diagnosis rates have gone up because it’s recognized that those therapies can help kids. And so, people are motivated to identify these problems in their kids when they’re young because that’s when it’s possible to maybe catch these things and help these kids and to the rest of society.


Question: Are there promising new treatments?


Sam Wang: Well, one characteristic of autism therapy in the last few years has been basically taking autistic kids and seeing what can be done to help them.

I wouldn’t call it palliative but it’s in the category of helping kids who are already diagnosed with autism, who’ve already been through a lot of the developmental stages that lead to autism. And it’s… And in some sense, the horse is out of the barn and it’s a question of what you can do to help these kids to bring to them the kind of social skills that would help them work much better in society. I think treatment is a ways away. It’s not in the next 5 years or even next 10 years but I think that understanding the mechanism and development that lead to autism could eventually lead to some kind of therapy that could perhaps nip autism in the bud when kids are, when their brains are making these developmental choices early in life.

So I think it’s a ways off but I think the research starts pointing towards better therapies.


Question: How do savants’ brains work?


Sam Wang: There are cases of people who can perform astounding mathematical feats with their brains. And to my knowledge, it is not well-understood exactly what it’s doing there. One way to think about it is that our brains are kind of sloppy. We have these shortcuts and tricks that our brains honed over millions of years of evolution to come up with quantitative intuitions about the world. And there’s something that’s possible that most of us don’t have.

And what’s interesting is the idea that these people use other algorithms entirely. That, somehow, they run across to perform mathematical feats. I think it’s not well-understood and I’m not sure that we’re in a position, right now, to understand how they do that.

Well, Mozart had something going, right? Didn’t he write “Twinkle, Twinkle Little Star” when he was 6? Look, I mean, no offence to most of the world’s 6 year olds but most 6 year olds aren’t writing tunes that survive across the ages. So clearly, Mozart had something going.

In the case of Einstein, Einstein was a very, very smart man who, in his 20s, made a series of discoveries in rapid succession that completely ended our understanding of the world. But one thing he had as well was he was thinking very hard about these problems. He had a [patented] clerk job that allowed him to think hard about physical problems kind of on the side.

And so, he was given the opportunity to daydream a little bit on the job. And that was pretty valuable.


Question: Do brain gyms work?


Sam Wang: I’ve never been to a brain gym. And I think it will be a fun experience. So brain gyms, obviously, play in a fear that by not being mentally engaged, we will somehow, it’s a use it or lose it kind of thing. And there’s a grain of truth to this, which is that one of the things that you can do to keep your brain happy and functioning well as you get older is to have a mentally engaged lifestyle. So the number one correlative retained cognitive function as people get older is educational status.

And it’s not clear whether that’s because being educated gives you the tools to lead a more engaged life or whether, maybe, if you’re mentally engaged person, you might be the kind of person who would go to college and graduate schools. It’s a chick and egg problem.

But in either case, that’s the number one correlate. In general, individual tasks that you learn when you play brain games, you go to brain gyms tend to only increase your capacity at that particular task or task of that type and they tend to lead to small benefits. And so, I think a lot of these exercises don’t lead to large benefits.

Now, it could be that doing a lot of these different things is something like a full body workout, then it could be that there’s some moderate benefit. But I think the people who go to those should really remember not only the intellectual principle, right, a sound mind but also the sound body principle. And so, I think any such gym should include what we talked about earlier, fitness training.


Question: How do brains decline?


Sam Wang: So there’re different kinds of cognitive memory loss that occur with aging. Certain kinds of memory loss such as forgetting where your car keys are part of the normal process of getting older. In fact, memory peak surprisingly early at the age of 30 and then declines gradually with time. So forgetting where your keys are is not a cause of particular concern.

Then, there’s dementia, which is forgetting, say, that you, like the old saying goes that if you forget where your glasses are, that’s normal memory loss. If you forget the fact that you wear glasses, that’s dementia.

So just normal memory loss is not a cause of concern. It’s not well-understood exactly what physically underlies this, although plausible candidates are loss of the brain’s ability to form new connections or to easily modulate the weight of the connections between nerve cells, those are called synaptic weights.

And so, those will be the candidates for why the brain seems to be less plastic in certain ways as we get older. But it’s not super well-understood. Now, there’s another category of memory loss. The severe decline in the form of dementia. And the thing that’s understood there is that you can look in the brains of people who after death or diagnosed as having Alzheimer’s disease and they have plaques and tangles that appear to be either the causes of cell death or perhaps the residue, the aftermath of cell death. And these plaques and tangles seem to be at the root of certain kinds of cognitive loss. And that’s something that’s studied now. And it’s a pretty active area of research.

And the current goal is to try to find ways to [stay off] those cognitive losses by even a few years. Because as we live longer, having a few years becomes very important.


Question: What are the most transformative ideas in your field?


Sam Wang: So there are two kinds of ways that neuroscience may be transforming. One that’s internal to the field, another that perhaps links to the rest of society.

So let’s start with neuroscientists. One thing that neuroscientists are very interested in right now is understanding how genetics and development can lead to the wiring of a brain. And one thing that’s become very big in the last few years is the idea that we may start having enough technology to be able to completely map out a fairly advance piece of tissue, like part of our brains, or part of the brain of a mouse. And technologies are being developed to basically give us the circuit diagram.

So everyone’s heard of a human genome project in which you sequence the entire genome of, say, a human being. There’s something that is jokingly called the human brainome project, which is to come up with something analogous in terms of mapping a human brain both for long distances and also in detail. And I think that technology has a potential to be transformative to how neuroscientists think about the problems that they’re working on.

Now, there’s another aspect to that question, which is how neuroscience is going to transform or interact with the rest of society. And there’s two ways that that can happen.

One way is, I think, the medical way, which we all are thinking about. You ask me before about Alzheimer’s disease. As we start beginning to understand the brain as a biological organ, we can start addressing neurological diseases like autism, schizophrenia, Parkinson’s. And I think that’s something where there’s going to be huge advances.

And then, there’s this other kind of thing that’s not medical. Let’s call it philosophical. The idea that our brains underlie a wide variety of human experiences. So, for instance, criminality. What does it mean to be criminally capable? Economic behavior, what is it that causes an economic bubble? Why do bubbles form and why do they burst? What is it that makes us fall in love? What is it that makes us form friendships? Why do we declare war on people we’ve never met?

And all of these things are aspects of human experience. And, I guess, what I’m claiming here is that as neuroscience advances, we’re going to start understanding all of these things in terms of brain mechanisms. And I think that all these things are old things that have been with us for… from time immemorial. But, I think, that as neuroscience advances, they’re all going to look a little bit different.

If people are interested in the brain, I mean, at a very basic level, I think our book, “Welcome to Your Brain”, is something that’s fairly introductory for people who have knowledge at all.

I think that one thing that people read if they want to keep up with current discoveries that’s always fun to read is the magazine “Scientific American Mind.” I know that I’m always learning new things from that. It ranges from discoveries that my colleagues are making about, say, how wheels work or how neuroplasticity may work to things that are very much concerns in everyday life like why is it that we are unable to imagine death or why do we procrastinate.

I find that that magazine is a great resource for people at all levels, both introductory and also very expert.


Sam Wang: I don’t know the answer to the question, is Google making us stupid. That’s a funny one.

I have to admit that I’m kind of stogy. I am a big fan of learning factual knowledge and having those facts at the ready. And I think that’s important.

And one thing I have very much notice is that this is something that is less empathized in my students and I think that’s going to continue in the future.

Getting back to the concept of fluid intelligence and G is that modern society for the last hundred years has increasingly rewarded reasoning skills and the manipulation of knowledge as opposed to the collection of knowledge.

I think that Facebook and Google are just the most recent manifestations of that increasing trend. My own view is that I think there’s a lot of value in the learning of factual knowledge. And I think that that is something that’s being lost.

But the thing that’s gained is that at the press of a key, you can get facts and start to manipulate them and turn them into something new. I think there’s a large gain and I don’t know how to trade-off those two things.


Sam Wang: Videogames have the potential for improving cognitive function.


There’s a researcher, Daphne Bavelier, who is very interested in the effects of videogames. So, for instance, one kind of thing that seems to occur is that videogames improve hand-eye coordination. And that’s a fairly obvious thing.

Depending on the type of videogame, say, for instance, if it’s a complex game like Sim City, that can lead to improvements in tasks switching. It seems likely, although I don’t think it’s been exactly demonstrated, it seems highly unlikely that videogames might improve multitasking abilities. There are limits to multitasking. Basically, multitasking, in most cases, leads to decrease performance in both tasks but at the same time, it’s a thing that it’s potentially trainable by videogames.


Question: Can computers outmatch the human brain?


Sam Wang: I think that what [Ray] Kurzweil does is take existing discoveries, whether being computer science or neuroscience and extrapolates to the maximum. So if you look in the “Singularity is Near,” he does a very good job of describing current neuro-scientific discoveries by my friends and colleagues and describing what’s been done. And then, he takes those and drives them up to the maximum possible interpretation.

So maybe we can observe a single synaptic connection being formed or breaking. That’s where the state of the art is. But that doesn’t mean that we can map an entire brain or copy a brain. That will be a massive technological challenge. So that’s one just an example of being a little bit too optimistic.

Another practical problem is that computational power is increasing tremendously and he calls upon that idea. But the fact of the matter is that energetic efficiency isn’t quite increasing enough to keep pace. And so, for instance, he likes to cite the year 2020 as a time when we can have something about the size of a brain that will compute as well as a brain does. But it looks to me like, looking at those trends, that the amount of power that such a thing would consume will be about as much power as is consumed by all of Washington D.C. So there’s a practical issue there.

Now, if brain function is ever replicating in any meaningful way, it’s probably going to rely heavily on the idea that we’re going to start understanding the heuristics and the non-algorithmic principles underlying how brain works. So looking at real brains, for instance, looking at how we use emotions to guide decisions or looking at the shortcuts that actual brains use to make decisions and to assign value to things. Those things are very much the meat and potatoes of current neuroscience and where neuroscience is headed.

So it’s possible to imagine using those principles to make better computing devices. But I think that replacing our brains by the year 2020, let’s just say I’ll be willing to place a very large wager against that.


Recorded on: April 24, 2009.