INSIDE THE TEEN BRAIN
photo of bruerinterview: john bruer

What is the "myth of the first three years" that you talk about?

The myth of the first three years is an idea that draws on some well-established results in developmental neuroscience. [First], developmental neuroscientists have known for 20, 30, 40 years that there is a rapid increase in the number of connections in the human brain -- and brains of other animals -- after birth. [Second,] they've observed that there are critical periods in the development of things like vision and first language learning. [Third], other scientists have observed in rats, at least, that when these animals are put into a complex environment, there seem to be changes in the brain that signal more synaptic growth in the enriched or complex environment.

Those things are well known individually. What the myth does is to weave those three ideas together to try to make a very strong story that brain science tells us that the first three years of life are an absolutely critical period for brain development. But when you pick apart the three strands, you can't make that strong of an argument. It's a myth.

Really, though, what's wrong with putting that forward?

If our intent is to use science and research to form policy, to guide educational practice and to give parents assistance, it's incumbent on people putting forth those arguments to get the science right. If they choose not to get the science right, if they choose to misinterpret it or over-simplify, we just have another instance of political rhetoric. ...

How would you characterize the 1994 campaign that Rob Reiner started on behalf of small children? You've used strong words to characterize those campaigns in your book.

The early campaigns really selectively chose very dated pieces of neuroscience and knit them together in a compelling way to sell a story. And the way that those campaigns were put together was pretty much in the same way we would put together an ad campaign or a publicity campaign for any other cause. There's a place for that.

However, when people claim to be telling us their policy recommendations are based on science, we should be sure that they are. Maybe one of the most unfortunate things I think that developed in the campaigns -- "I Am Your Child," for one -- is the suggestion that there's a very close relationship between brain research and research on attachment theories -- developing this affiliative bond between an infant and a caretaker. Attachment research is an important piece of research on child development. Brain science is a very important part of what we might be able to use to help children.

But to date, there is no research that links attachment with brain science. And frankly, many brain scientists are just puzzled by what attachment theory is about. So in that area, what needs to be done is for scientists of various disciplines to sit around the table, state what they believe, what they do know, and begin to ask, "Well, how can our science support your claims? How can yours support ours?" But we have to do the research. We just can't speculate on these things. ...

The "I Am Your Child" campaign raised billions of dollars for early childhood education. Witness the $700 million, at least, in California, from the tobacco tax. What could be wrong with that?

Well, yes, one would think that raising $700 million or whatever it is for early childhood programs couldn't be a bad thing. And in many ways, it isn't a bad thing. However, the real problem here is what are you going to do with that money? If the interventions that are going to be put forward are based on scientific arguments "I Am Your Child" put forward, we're doomed to wasting $700 million. ...



Bruer is president of the James S. McDonnell Foundation in St. Louis and the author of The Myth of the First Three Years: A New Understanding of Early Brain Development and Lifelong Learning. He argues that advocates of the "critical periods" theory of brain development have misinterpreted the research, resulting in a potentially disproportionate channeling of resources toward early childhood education.

The Carnegie Foundation report "Starting Points" was an attempt to mobilize public interest to get legislation for early Head Start going again. But the brain science was included in that policy statement almost by accident. And what's puzzling about this whole story is "Starting Points"-- I believe it's a 132-page document. There are two paragraphs on page 11 about the brain. But if you look at the press coverage that report received -- and it's press coverage the report should have received, because it's an important piece of work -- all the press talks about is the brain.

This simple popular news weekly magazine idea that adolescents are difficult because their frontal lobes aren't mature is one we should be very cautious of.

Now, why is that? One hypothesis is that it was promoted that way. A second hypothesis is that we're all just so fascinated about a brain-based or neural-based explanation for what we want to do, that somehow the brain data is more real. Even if it's only two paragraphs out of 132 pages, that's what we look at. ...

You made some suppositions in your book about why the brain science part of this argument was so compelling, so seductive. What were those?

... It seems that, when it comes to policy or science or parenting or health, that somehow biology is real science and behavioral science is not. ... What's really unfortunate about that approach is that we have much more to learn from behavioral science about educating and raising our children than we do from brain science right now. ...

What sort of things do you think we can learn from behavioral science?

Take for example, claims that we find in the myth literature that the ages from zero to three or zero to ten are the most crucial times for learning -- a time when children learn more quickly and efficiently. What's interesting in the myth literature is that people who make those claims have not looked at any specific cases of learning anything.

When you do look at children's ability to remember what objects they've seen, to remember what places a toy is hidden in, you see that children's ability to learn those kinds of things increases from the first years of life through adolescence in an inversely proportional way to the number of synapses they're losing. So this idea that you learn best when you have the most synapses is patently false when you look at learning curves for various tasks.

Furthermore, what we do know about learning based on 25, 30 years or more of research in cognitive developmental psychology, is that you learn most easily and most quickly if you have a sound understanding prior. Your prior knowledge is the best predictor of how quickly and well you will learn. You can look at word learning, for example. The more words people know, the more quickly they'll learn new ones. So this notion that rate of learning is so closely linked to the biological maturation of the brain isn't a very useful one.

If we wanted to improve instruction for children, young children, what we should do is try to figure out what do they know before instruction; what do we want them to be able to do after instruction; and how working from what they know already can we design an instructional environment that will take them from where they are to where they want to be. ...

Where do the children get the prior knowledge?

It's certainly from their environment. There was some very interesting work done by the late Robbie Case at the University of Toronto and his colleague, Sharon Griffin, who's now at Clark University, looking at children who enter kindergarten with a severe deficit in numerical understanding. The general assumption was that these kids just weren't generally too bright. What Robbie and Sharon found was that's not the case. There are very specific things these children don't know.

One of the most interesting things these children with learning problems have in the domain of arithmetic is not being able to judge which of two numbers is bigger. They can't compare numbers for size. That's a very strong predictor of how badly they will do in early formal mathematics instruction. What Robbie and Sharon did was to develop a test to assess children's number knowledge prior to school, and then develop a curriculum based on that knowledge that would take them to a typical formal early mathematics curriculum.

What's interesting is children's number knowledge varies by the social class they come from. It's not an ethnic thing. It's the socioeconomic status of the family that predicts this. So there is something going on in the households of people from low socioeconomic status homes that prevents their children from coming to school with the same prior knowledge of numbers middle-class kids have. When you fix that, which you can do in a year, these children who were formerly at risk for failing early mathematics perform comparably to Japanese students on tests of numerical calculation.

The other thing we have to realize here is this inability to learn numerical concepts, or this deficiency that children might come to school with, is not a biological constraint; it's very much a cultural one. And there are other studies of adults in areas of the developing world who, for whatever reason, had no need to learn how to compare two numbers for size. They didn't have money. They just strictly bartered things. And you see the developmental trajectory these people take quite late in age is exactly the same ones that four-, five-, six-year-olds in Western industrialized society takes.

So it's not a biological brain maturation issue. It's cultural experience in your environment. And we have to be very careful not to confuse the culture with the biology.

Given that, wouldn't that also argue for early Head Start and other very good preschool programs?

... Children have to be ready to do certain things by age five, by age six, by age seven. When they enter school, some children aren't. If we can identify those children and help them acquire those skills, by all means, we should do it. But it's not going to improve our track record on that by thinking it's something to do with the special learning abilities of their brains at that time. This kind of compensatory help could be provided to children at any age. ...

Rather than emphasize early childhood, the bigger challenge is to say, "Well, a citizen of any age that wants to learn something -- how do we design learning experiences and environments that will facilitate those changes?" Children can benefit from that research; adolescents can benefit from that research. So can adults...

Given that there's a finite pot of money -- we don't have tons and tons of money -- I hear underneath, possibly, although you don't really ever state it very clearly, a plea to shift resources. What do you think of where we are spending our money right now?

... Our challenge is to try to figure out how to use the science to maximize our return. Now, investing more or all of it in early education as opposed to remedial work in the early grades or even junior high school and high school may not be the best return on our investment. ...

Why were you criticized when you criticized the "first three years" movement?

A lot of the criticism seemed to result from my criticizing the scientific basis of an argument that was used for ends which everybody thought were commendable. I think if we're talking about policy and reasons for doing things, and if we're appealing to scientific evidence rather than what people feel or the latest poll, it's incumbent upon people who make those arguments to present honest arguments.

So one thing that's been positive about the book is I think it has encouraged scientists to step forward and be more critical about how their work is used and interpreted in policy arenas and in the general media. What is unfortunate about it is many of the people who advocated this argument in the first place have been unwilling to engage in a scientific debate about the claims. ...

When the Bell Curve came out, there was a huge uproar about the bad science because of a conclusion people didn't like. Here we have a case of equally bad science, for a conclusion people do like, and [we're] not being nearly as critical. And we should be...

What do you think of the research that Dr. Giedd has done at the NIMH about the explosion of growth in pre-adolescent, a young adolescent brain, and then the pruning of that -- particularly the cortex, the frontal cortex?

... What Dr. Giedd's work seems to be indicating to me is a further confirmation, or corroboration, of things that we'd known for 20 or 30 years. We've known ... that different parts of the brain mature or go through this explosive growth in connections at different points in development. Dr. Giedd's work provides us another way, another means to establish that same finding.

Talk about the brain a little bit and how it grows, and about this plasticity issue.

This issue of how the brain changes by itself or with experience, brain plasticity, is actually a very complicated one. What the discussion about early childhood and even adolescence has focused on is this explosion of synaptic neural connections in the brain. We've known for 20 or 30 years that this explosion of connections occurs at different points over different time courses in different parts of the brain. These areas of the brain Dr. Giedd is studying have been known to be the last such area that matures.

It's not at all clear what experience has to do with that. In fact, many argue -- and I find the argument compelling -- that this explosive growth and even pruning of synapses is pretty much independent of the environment people find themselves in. It happens.

What we really have to be careful of here is if we're talking about how fast three-year-olds learn or what kind of moral decisions teenagers could make. The relationships between the behaviors and the desired behaviors and the brain structure is totally unknown. So this simple popular news weekly magazine idea that adolescents are difficult because their frontal lobes aren't mature is one we should be very cautious of. ...

This notion that there's going to be some easy connection between counting synapses or measuring white matter and the kinds of behaviors people display or we want them to display is one we're going to have to do a lot more work on before it's science.

There was a period of time that parents were exhorted to play Mozart for their babies, have flashcards, use black and white mobiles to create what were called in the literature "enriched environments." What do you think of those ideas?

In recent years, one thing parents have been preoccupied with is providing enriched environments for their children including playing Mozart, getting flashcards, one sixty-fourth model reproductions of Calder mobiles and things like that. All those things probably make the parents feel a lot better. But it's probably not doing a whole lot for the child.

Let's look at the mobiles, for example. The visual system does need input to develop. What it needs, however, is normal experience that's all around us. It doesn't need special input. So the pretty mobile has some emotional appeal to the parent and maybe the baby; that's great. But to think that that has some power to increase the rate at which the visual system developments or visual acuity or any of these other visual functions -- there's no reason to think that.

The Mozart effect is truly fascinating. Originally, some researchers found that if they played snippets of a Mozart sonata to college students, there was an increase in these students ability to do spatial mathematics or reasoning. A "long-term effect," it was called -- here, "long term" is 15 minutes. So based on the college research and all this interest in the brain and how wonderful Mozart is anyway, policies were put forward here by several governors in the United States to give us a Mozart CD or a classical music CD to every child in the state. Again, that could be nice for the parents and the baby, assuming these households had CD players.

But the researchers who did the original work pointed out nobody knows what happens when you play Mozart for a baby, because nobody has done that study. So this is an instance of looking at something that showed, actually, a relatively short-term effect compared to the time scale of life in college students on a very particular task to making some kind of mass policy for infants, when no research at all existed.

What was the effect on parents of these kind of exaltations?

I think exaltations and the activities like the Mozart effect or worrying unduly about the environment you are providing your child created a lot of guilt in parents. I think parents were desperate and being made to feel more so that they were failing their kids. And it's a shame that that happened, because parenting's hard enough anyway. ... The thing that's been most, I guess, moving to me based on the book I wrote ... is that a lot of parents were really relieved to hear it's not all as crucial or critical as they had been led to believe. It's not all over by time they're three. ...

Are there critical periods in brain development?

Yes. ... There are critical periods for acquiring certain kinds of skills and abilities. But it's very important that we be specific about what kinds of skills and abilities we're talking about. Back in 1986, one of the first volumes that attempted to integrate brain science with early childhood was an issue of Child Development contained an article where the lead author was Bill Greenough. And Bill introduced the terms "experience-expectant brain change or brain plasticity" and "experience-dependant brain change."

What Bill meant by "experience-expectant brain change" is that, given our evolutionary history, humans, like other animals, are born into the world expecting to find certain kinds of experiences. This is the ecological niche they've been evolved to develop within. So for things like seeing, hearing, first language learning, there certainly seems to be critical periods for the development of those skills.

But what we have to realize is the kinds of experience we need during that critical period is everywhere around us. It's not something we have to go out and provide children. The experiences for your visual system or your first language system to develop are there in any normal human environment, where normal encompasses a pretty broad spectrum from Manhattan to Toronto to Outer Mongolia. It's pretty much the same.

The other kind of brain change ... is "experience-dependant brain change," experience-dependant brain plasticity. By this, Bill meant that there are other kinds of things we have to be able to learn throughout our lives. We have to learn to negotiate the particular environment we live in. That can vary with geography. You can vary with culture. They are not species-general skills, but they're skills that are very specific to individuals. It seems that there's no critical periods for that kind of brain change. Those are the kinds of things we go to school to learn, the culturally transmitted skills.

And it's this distinction [between the kinds of brain change] that's been lost in the popular and policy discussions. ... People have [equated] this "experience-dependant" change to "experience-expectant," [and have come to believe that] brain development in general is constrained by a critical period. That's not the case.

It's important again to keep in mind [the difference between] the kinds of brain changes that occur in normal development, where the only way you can stop it is to lock your child in a closet for years, versus the kinds of experience children need to learn how to read, to learn how to play a musical instrument, to learn how to play hockey. And there's no reason to think these [kinds of cultural skills] are constrained by critical periods at all. ...

What have we learned about brain science over the last ten years that can help us rear our children?

Brain science has told us very little about what we can do to raise our children and raise our children better. ...

It's very frustrating, as journalists -- and I think frustrating for a lot of people -- to look at this academic work, to look at this brain science, and be constantly told that it can tell us very little and tell us nothing. These are funded by taxpayers. There's huge amounts of money going into neuroscience, going to psychology departments. And often you sit back and say, "My gosh, what are they saying to us?"

I say a couple of things. We've invested in a lot of science that's very good; we can use right now. It's called cognitive developmental psychology, behavioral science, sociology, anthropology. We should use it.

The other thing we have to realize on the brain side is that neuroscience is a relatively new discipline; in particular, this area of systems neuroscience and brain imaging. These are techniques that have only been around for 20 or 30 years. So to think in that space of time we're going to develop the neuroscientific equivalent of penicillin is really unrealistic.

So I think part of the journalists' and the public's frustration is, again, the misuse and misinterpretation of the science to create the belief that tomorrow some brain-imaging study is going to tell me what I should do with my teenagers this weekend. That's not going to happen. ...

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