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