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Building the costly human brain: implications for the evolution of slow childhood growth and the origins of diabetes
Christopher Kuzawa, Northwestern University, Evanston, USA
Friday, Oct. 23, 2015 · 10:29 a.m. · 28m 03s
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Therefore to be here I really
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appreciate the invitation and I've
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learned a lot and like many of the
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speakers before me I'm rather
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neurologist or nutritionist. And the
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biological apologist and actually my
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work generally has very little to do
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with the brain most of what I do is in
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the Philippines I work with the study
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in a place called subdue. We're there's
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a protocol for that's been going for
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thirty two years tracking mothers their
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offspring and the grand offspring no
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more than three decades the data we use
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these data to look at the long term
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effects of early environments stuff
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related to what Steve Matthews was
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talking yesterday we also look at
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ageing genetics subjects all sorts of
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things going on to talk about any that
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today talk about a different questions
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I've been thinking about and writing
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about for about twenty years since
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graduate school. And that is how did
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humans manage to of all such large
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energetically costly friends. And this
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is particularly an important question
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early in life because the brain is much
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larger really for this figure batted
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around that about twenty five percent
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of resting metabolism goes to the
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brain. But does I'm gonna show you that
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that number is much much greater during
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childhood. And I think this has
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implications for understanding the
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evolution of the human pattern of
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growth in our life cycle. And it also
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will have connections with things like
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cognitive development and also possibly
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you origins of diabetes. So I'm gonna
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start with a short preamble because I
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am gonna come back to this point about
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died ease at the end I just wanna set
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up some of the literature that sort of
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motivate that question we already heard
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about some this may take many people
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familiar with that this is the work of
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David David Parker showing that if
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you're born low birth weight or lower
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birth weight you have a higher risk for
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cardiovascular disease. And he propose
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this model which I think is stood the
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test of time pretty well at this point.
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I think this that's undernourished or
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stress is gonna slow its growth rate.
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But also modify all these other
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biological systems in ways that are
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relatively permanent or durable and
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persistence later live to influence
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your longterm risk for chronic disease
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and some of this is that the genetic
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and some of this involves both of
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organs and so on. And so this is pretty
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well established at this point I think
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many people are aware of it but these
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processes to not in the bar thing they
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continue in the post it appears in fact
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there's a lot of evidence that if you
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want small long term health
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consequences are actually much worse if
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you if you manage to grow quickly after
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birth. And so the general finding like
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I said I think words small you end up
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getting more visceral for minutes then
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resistance among other traits and so
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just a couple quick examples of that
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this is the L aspects that in UK
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individuals who who experience catch
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approach between in the first three
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years of life or more it's not
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resistant they have less insulin
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sensitivity at eight years of age now
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if you're less insulin sensitive them
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is that your your muscle in your fatter
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not responding tinsel and and not
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taking glucose of the bloodstream and
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therefore you're at increased risk for
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diabetes. And this is something very
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similar from to a so rapid growth in
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the first three years of life you see
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more insulin resistance okay now we can
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dig into this and try to figure out
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what the mechanisms are a cellular
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level of hormonal level organism a
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level. But the question I wanna post
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today is a little different one from an
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evolutionary perspective why does
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growth and everything challenging the
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matter why what is our body reset its
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metabolism its priorities with with
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where good causes used within the body
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in response to the nutrition that we
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experienced during this period. And I'm
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gonna tell you right now that I don't
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have a great answer for this I don't
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have a definitive answer but I do want
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to convince you buy yeah that we want
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to have a full understanding of this
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we're gonna have to take bring
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seriously because brain as we've heard
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is a major user logos. And as I will
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show is really dominating the body's
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metabolism at this age right and so to
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set this up go ahead and begin into a
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number of topics for the start by
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looking at the evolution from job
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growth some very unique characteristics
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of protein humans that differentiate us
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from other exclusive and then we'll
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talk about some of this research that I
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make probably collaborators of done in
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recent years that qualifies the cost
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the brain and looks at that
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developmentally. And then we'll have a
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few implications for international
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attrition at the end okay so let's
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start with this. Now this figure
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compares us to transparencies not
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chimpanzees are last common ancestor
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with James was about six million years
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ago your closest living relative fairly
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closely related to us now what you see
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here there's some obvious differences
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chimpanzees like other mammals. K they
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win their young at the age at which
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their offspring can fend for themselves
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and feed themselves which is about four
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and a half years of age so so chips go
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from breast milk to self provisioning
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and it's individually no two per se
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that's provisioned of course or
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offspring you know anybody who's
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dedicated knows that they're not to be
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able to feed themselves and talk quite
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a bit later than that probably five six
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or even later right and yeah we we much
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earlier than chance. So how do we pull
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this off. We do this by by for instance
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making maybe fruits weaning fits right
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processed food. And the other key
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factor is we're what is called a
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corporate of leap readings P C.'s in
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the sense that it's not just the mother
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that has to feed the baby is also the
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father grandparents older siblings
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other individuals like many people end
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up eating the final suburban is not
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just on the mother now what this allows
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us to do with this P C.'s allows us to
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win early which means ovulation resumes
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earlier which means that there's a
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shorter number interval infertility is
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higher. So revolutionary biologists
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this is kind of a no brainer why this
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system would actually processed right
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because there's a a clear evolutionary
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advantage to it. But the other piece of
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the story that you can see is the fact
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that the blue line so much longer right
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we also delay the onset of adult but we
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continue growing much longer. And so
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this piece he's been less well
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understood why better growth slows so
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much and if you think about it we grow
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for much longer and we don't end up to
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be this I smell sense right I mean
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where we have about the same size as
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chimpanzees so clearly our growth rate
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must be a lot slower. So let's take a
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look at just tell slower growth is
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gonna start with this maybe no this
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this is the clever line relating
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metabolic rate body size across
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different species. And you see that
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both of these scales are lot lot plots
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in the exponent hears about point seven
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five so it's less than one with this
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means is that you as you go from a to
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larger body organisms metabolic rate is
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of course increasing record
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expenditures increasing. But it's
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increasing at a slower rate than great
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again way right so okay a gram of
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elephant uses about one eighth the
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calories as a of a gram of models that
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that kind of idea there's an increasing
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efficiency have given that metabolic
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rate scales in this way okay to body
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mass it makes sense that other
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components of our metabolic expenditure
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also scale this way and we see this
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with rate. So these are data compiled
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by case some decades ago showing
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mammals and reptiles and the first
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thing and this is growth rate between
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birth and about forty percent of adult
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size with roughly the time frame of
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childhood that we're thinking about
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first thing I want to notice the
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scaling coefficient is about the same
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right so it it it agrees but that that
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clever line the second thing is that if
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you look at mice rats guinea pigs and
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sheep okay major experimental animals.
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They're right on that line they're very
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well behaved matt most of the good what
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also makes sense is down below you have
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the right files another cold blooded
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right so for any given body mass big
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spend much lower calories than the
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comparable size mammal in some actually
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they have less calories to expand on
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growth and have slower growth. So that
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all make sense which doesn't make sense
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is why humans are on the on the rep
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line yeah this is where the story gets
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kinda I so if we take this line if we
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just look at these pieces that are
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right in our body size here. And
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plopped down in order ideas about the
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mammals of our size and you can barely
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even see the human mind right where are
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it's orders of magnitude slower and
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these other species and if you compare
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us to direct files will look like a
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pencil. So there's something very
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strange going on here right human go at
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the base of a reptile during childhood
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why is this. Now one idea that's been
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cited and you watch a literature for a
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long time is that building the human
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brain is unusually costly this is
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required a slowing of growth and this
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is just kind of an intuitive idea that
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people are batted around it's never
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really been tested but it's it's I did
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a fair amount is is a one plausible
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idea. And the problem is how do you go
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about testing it well personal here
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here you see the increase in brain size
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of about four million four million
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years an SP C.'s rights were very and
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supplies has been an increase in brain
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size of maybe a factor of three or four
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during that period. And primates as a
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whole compared other mammals a very
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large brained yeah these are this is
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just limited to the age that you're
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even larger brain that were very top of
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the heap right so we have very large
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brains in they are costly as we've
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heard about so if you compare a gram of
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muscle tissue in the adult to a gram
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brain it's about fifteen times more
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costly right. And and so you're sitting
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here at rest and your bodies are giving
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of energy about the rate of a hundred
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Watts sickening at the room at that
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rate twenty of those what's your brain
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and that may seem kinda DM you know
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it's not not particularly bright but
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it's actually it's actually pretty
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remarkable because if you look at this
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P C.'s most on the order of about two
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three percent of the metabolism ghost
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right right so we're we're different
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other primates which their data around
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ten percent and the name the human
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again it's about twenty percent as we
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parted now I'm actually case against it
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all in the newborn the the brain is
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much larger relative to the bodies this
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figures can be much higher. And the old
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estimates from the literature have that
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figure in sixty percent okay so early
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in life the brain really is dominating
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the body's energy budget in a way that
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we can imagine might actually lead to
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trade off approach right maybe some the
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calories ago drove me to subsidise
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their brains now if that's true then we
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can come up with a hypothesis and some
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some ideas that we can test so far
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costing brains explain or slow growth
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the ages of slowest body grows should
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also be the ages of highest brain
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energies right you just won the brain
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really demanding a lot we should see
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growth slowing down a lot and so we can
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look at this again by by looking at
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percentage of arm are going to bring
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what if you think of the body's energy
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budget is applied what fraction of that
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pie is being dominated used by Bryan
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what how much is left over for other
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functions this tells us something about
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how how demanding the brain is for the
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body that each. Now the problem is that
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we don't know a lot about that until
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recently we don't really know
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developmentally how that figure a
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percentage of one part of the brain
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changes no one side of one approach
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that's been taken is to take the
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expenditure programmer brain yeah
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multiplied by the size of brain a
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different ages and then divide by the
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resting metabolic rate. And this is in
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fact what was done by holiday to this
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the expenditure lead operating. And
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then multiply that through and then
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divided by remind this is the data you
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know kind of connected here sure graph
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and this figures inside a lot came up
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with this estimate that eighty seven
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percent of our more goes to the brain
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or I've always had problems with that
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figure that doesn't that doesn't seem
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possible to me because that least
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thirteen percent of the body's
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metabolism to do everything else. You
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know apart and so on the organ. So we
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seem like an overestimate and also if
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this is in fact the nature of the that
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development change bring energetic then
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there's no evidence for trade off
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between growth rate and brain
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metabolism because each one by go
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through the slowest K which isn't child
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about four to five years of age is not
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an age when the brain isn't speeded
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anything it's kind of midway down in
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declining right. So if anything these
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graphs or more parallel then suggesting
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a trade off right. Now the problem with
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this is that this assumption that that
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a gram brain cost the same a different
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ages is wrong and that's not surprising
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because there is a lot of activity
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going on early in life. Uh yeah yeah
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that we've already heard about and
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we'll get insights into this from pat I
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imaging positron emission tomography
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this is a method this is not something
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I do better collaborator does where you
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give radio labelled glucose right it's
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tracer. And then you can measure the
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rate of glucose uptake in in the brain
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you get this kind he map that tells you
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about the of wood energy use. And here
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it should only back to nineteen eighty
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seven published this classic paper
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quirky compiled up at data from his
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from his clinic on kids bearing in age
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from birth to adulthood. And here's
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some adult controls at put a red line
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through there for comparison what you
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see is that each grammar brain missus
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cortical uses glucose at a slower rate
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than the adult one at or okay and that
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X increases a lot about twice that
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level in in childhood and then
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gradually declines rights as a lot of
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dynamics in the rate of glucose uptake
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per unit unit grammar bright. So what
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underlies this what this is all about
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largely about Sinatra genesis a lot
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about a costly synapses are part of the
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way the brain develops is proliferating
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extra synapses and the menu zero or
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more U speaker is different parts of
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your brain you actually firing those
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circuits and and they stabilise and the
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circuit in the in the synapses that
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don't get fire eventually get from the
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way. So you get this initial
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proliferation in the pruning away right
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and this is a costly process you can
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see really on there's skills related to
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just hearing inside and then there's
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language after that and then you get
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higher cognitive functions that are
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spread out over a longer period and
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we've only heard much more about
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synapses and and and their energy
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metabolism the bottom line is they have
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constant requirements for energy knee
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eighty P to maintain the gradients of
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potassium and calcium and so you about
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and which allow under our fire and so
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here you see so not the genesis this is
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the actual synaptic densities there's
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not many data on this this is a classic
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paper from nineteen seventy nine by
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heart locker you see the rise of
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synaptic density in the early years by
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picking on childhood big gap and data
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but eventually getting down to a dull
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levels later right and so this is
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snapped genesis and this is the process
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of prejudice talked about so this is
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largely what underlines the these
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dynamics these this is reflecting
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changes in the density of synapses
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which are energetically costly what
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this all means is that this this big is
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gonna have to be biased right at or
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this is all right because as I showed
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each triangle brain actually has a
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lower metabolic rate it more that any
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adult right so that's an overestimate.
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But as I noted it rises to about twice
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the adult level child and so this is an
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underestimate and we kind of
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hypothesise that they might the curve
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might look something like this. What
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you take all that into account. And so
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that leads me to the second point of my
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talk which is our recent study that
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tried to pull together data and
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quantify all this these are some my
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colleagues my collaborators on that's
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from northwestern Wayne state George
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Washington university Harvard and mount
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Sinai hospital okay so we started
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really quickly is a very truncated
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overview the methods we started to
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going these data that data that irish
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or do use three Bram cerebellum brain
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stem sets separate curves to these
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these collectively give us the E
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glucose uptake by the entire brain that
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gives you the energetic cost program of
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tissue so we also need to not
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milligrams there are and we got that
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from M alright data there's an
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indication longitudinal study that we
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mostly. And nick laying was for that
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study was was also on this paper and
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then you do all the math you get total
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brain costs do that for each age right
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and this is what you get so this is
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what it looks like no we that a fifteen
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years of age because that was the last
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at that data. And I got the adult level
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down here now grams of glucose per day
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is picking out in about five years of
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age. There's about a ten percent
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difference your that's because males
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are about ten percent larger about the
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bodies and brains so that's all that's
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going on there but what's remarkable
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about this is that it five years of age
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the five year olds brain is using twice
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the glucose of an adult right. This
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remarkable because their brains uneven
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full size yet yeah and more importantly
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their bodies are about one third the
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size. So is a burden on the body this
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is really significant right and so we
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wanna be able to quantify that and so
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the next step is to convert these grams
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of what goes into kind of glory
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equivalents and then divide by resting
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metabolic rate to get a sense for what
00:16:50
percentage of the bodies are Mars going
00:16:53
to the brain like I showed earlier and
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this is what those figures look like
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speaking out and about two thirds of
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arm are and about five years of age
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right so this is this is really
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substantial I it's really dominating
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the body's energy budget and so this
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trickster question right this this gets
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to the point that I start to address
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our ages of high brain glucose use also
00:17:17
ages of slow waking and vice versa yeah
00:17:20
the answers yes so let's take a look at
00:17:23
here this is we philosophy calculated
00:17:26
just as the first derivative of this
00:17:27
cross sectional data that we're using
00:17:29
in the brain states of body sizes of
00:17:31
the same individuals. And it's in all
00:17:33
what's occurred estimate but it gives
00:17:34
us a sense for kind of for weight loss
00:17:37
sample converted it as the units
00:17:39
standard deviation unit so it's you
00:17:41
know this little post upon that because
00:17:44
this is what it looks like. So the age
00:17:46
at which glucose uses that it's maximum
00:17:49
is the age at which buddy way growth is
00:17:51
at the minimum. Now we can go one step
00:17:53
further the mess and it's not a parties
00:17:55
both verses age we can plot one versus
00:17:58
the other in if there's a trade off
00:18:00
between them we should expect an
00:18:02
inverse when your relationship between
00:18:04
the two right is the brain becomes more
00:18:05
costly both reach should go down and
00:18:07
vice versa. We plan on that way this is
00:18:10
what we see no this was a perfect
00:18:12
inverse linear relationship it would be
00:18:14
that great dotted line so I think we're
00:18:16
pretty close. So let's take a look at
00:18:18
what's going on here. So each of these
00:18:20
is a different age we're kinda Tracy to
00:18:22
like her so it's go between one and two
00:18:24
years of age if you go from one to to
00:18:28
the brain is increasing its dominance
00:18:30
of the body's energy budget this is
00:18:32
partly because of growth and partly
00:18:33
because of synapse genesis one of those
00:18:35
processes are happening. That's
00:18:37
increasing at the same time we
00:18:40
philosophy is decreasing right and
00:18:42
you'll notice that each is about one
00:18:43
standard deviation unit meeting that
00:18:46
they're proportionate other
00:18:47
proportionate inverse changes happening
00:18:49
in each here you get to this point. And
00:18:52
this is the point where the brain is at
00:18:54
its maximum in terms of in the body's
00:18:57
energy by trade rightmost point. And
00:18:59
it's also sorry. It's also the lowest
00:19:03
growth lassie right so this is the
00:19:05
point where the P in brain energetic
00:19:07
score insides of the trough. And weight
00:19:09
gain and on the other side we reverse
00:19:11
that's right so from seventy eight
00:19:12
years of age the the brain is starting
00:19:15
to decrease in instalments the by this
00:19:17
is because it's not a pruning. And at
00:19:19
the same time you know about a
00:19:21
proportionate increase in weight loss.
00:19:23
So I think we have really strong
00:19:24
evidence here that there's a you know
00:19:26
there's been a trade off between these
00:19:28
and this is what it looks like an
00:19:30
females and similar but Peabody happens
00:19:33
earlier. So things change an earlier
00:19:35
age. I okay outside twenty minutes and
00:19:40
I'm gonna we're gonna have a lot of
00:19:42
time for discussion so let's go back
00:19:45
and and you know where I began here
00:19:48
humans have this very unusual life
00:19:50
cycle where we really sort our growth
00:19:52
rate. And I think we've got some good
00:19:54
insights into why our brains are
00:19:56
incredibly costly. So costly that some
00:19:58
of the calories that would have been
00:20:00
going to growth are actually going to
00:20:01
the bright right yeah and so I'm gonna
00:20:05
dig into a couple the implications of
00:20:07
this for international attrition and
00:20:11
one are coming back to this point about
00:20:14
diabetes than to talk a little bit
00:20:15
about cognitive development which I'm
00:20:17
sure the next week is gonna have much
00:20:18
more to say about right so we show this
00:20:21
graph showing this is evidence that
00:20:25
effectively calories got are going from
00:20:27
body growth to glucose right at this
00:20:30
age of very high bring requirements one
00:20:33
implication of that is that that
00:20:36
deposition grinds to a halt. And so
00:20:38
this is all I did here was take some
00:20:40
kind of reference data on body
00:20:41
composition multiply through by the
00:20:43
body weights in the sample. And then
00:20:45
get an estimate that mass and take a
00:20:48
derivative of that to tell you kind of
00:20:49
the the velocity of that deposition how
00:20:51
that's changing so it birth there's
00:20:54
about three kilograms per year if they
00:20:57
were to keep growing at that pace you
00:20:58
know so much bad as being deposited.
00:21:00
But by the age of the peak in the brain
00:21:02
energetic it's down to about ten grams
00:21:04
per year right so basically comes to a
00:21:06
halt yeah this is interesting because
00:21:09
it gives us some insights into some
00:21:11
other patterns that we know about the
00:21:12
fact that it shows can fold levels
00:21:14
right so at a posse and be on my bottom
00:21:17
out at about the same age that the
00:21:19
brain is at its peak I know this is
00:21:22
interesting because the suggested the
00:21:24
brains needs are peeking out at an age
00:21:27
when we have our lowest energy
00:21:29
reserves. Now this is important because
00:21:32
unlike other tissues in the body the
00:21:34
brains metabolic rate is relatively
00:21:36
stable even your sleeping it still
00:21:37
using a lot of energy. And if you're
00:21:40
under nutritional stress or starvation
00:21:42
for instance you still have to to make
00:21:45
me those basic energy energy needs
00:21:47
right. And so there's an interesting
00:21:49
dilemma here and you can think about
00:21:51
this with an analogy I mean many of you
00:21:53
have mortgages on your houses and you
00:21:55
have to pay that mortgage every month
00:21:58
in if you lose your job is to pay the
00:21:59
mortgage or you have to foreclose on
00:22:00
the mortgage right. So you better have
00:22:02
something in savings to pay it now if
00:22:05
you have bigger mortgage you're gonna
00:22:06
need have a bigger savings account in
00:22:08
order to make that mortgage payment and
00:22:10
avoid foreclosure it's completely
00:22:12
analogous to what we have here. Because
00:22:14
during childhood sixty six percent of
00:22:17
the Charlton comics going to a mortgage
00:22:19
rate in that means that if there's a
00:22:21
kind of a bad that disrupts their
00:22:22
intake they better have a you know a
00:22:25
all sizeable savings account to draw
00:22:27
from but in fact it's at its lowest
00:22:30
point a life cycle so we have a bit of
00:22:32
paradox here. How can we have this very
00:22:34
precarious situation and I think that
00:22:37
this gives us some insights potentially
00:22:39
in to some of the things that I said at
00:22:40
the beginning okay relating growth
00:22:43
diabetes was a reminder you know growth
00:22:46
restriction followed by rapid hosting
00:22:48
awaking leads to the following okay we
00:22:52
need is favoured I'm sorry as you gain
00:22:54
weight papers fat overly the end up
00:22:56
getting more fan that fact is
00:22:59
preferentially deposited in the
00:23:01
visceral depot. And that's important.
00:23:03
Because the blissful depots actually
00:23:05
different than other people's in the
00:23:06
body it's inter name interrelated by
00:23:08
sympathetic nerve fibres. So when you
00:23:11
experienced rescinded run one part of
00:23:13
what's going on is the germans being
00:23:15
released in that the in fact is being
00:23:17
released immediately so so there's
00:23:19
people only other depots is actually
00:23:21
part of a short term energy balance
00:23:23
regulation much more so so that's
00:23:25
interesting and then muscle as I've
00:23:27
already pointed out is insulin
00:23:28
resistant right. And so if we think
00:23:31
about of course these contributed I D.s
00:23:33
but thinking about it functionally we
00:23:35
might think of these as ways for the
00:23:37
body to buffer the brain and so let's
00:23:39
take a quick look at how that might
00:23:40
work. So here we have by that Lever
00:23:44
muscle and brain. And if you experience
00:23:46
starvation or other some other stress
00:23:48
or that that cause you to to break down
00:23:50
track less rights you have direct
00:23:53
buffering of the brain okay let's all
00:23:56
enters other liver is a good idea
00:23:58
agenda substrate becomes glucose and
00:24:01
feeds the brain directly you also have
00:24:03
free fatty acids which got the labour
00:24:05
and lead to the formation of key
00:24:07
channels that are taken out of that are
00:24:09
taken up by the brain preferentially
00:24:11
use this energy substrate is we have
00:24:13
direct buffering of the brain to that
00:24:15
but you also have indirect buffering
00:24:17
missus wherein spongy in insulin
00:24:18
resistance comes with free fatty acids
00:24:22
are in the bloodstream muscle becomes
00:24:24
instant resistant it starts using
00:24:25
glucose and uses preferentially uses
00:24:27
the the the fatty acids per substrate.
00:24:30
And this is the way. I mean I mean a
00:24:32
sense concerning glucose for more
00:24:35
important functions. This increases the
00:24:37
amount of because available to brain
00:24:39
indirectly right and so you can think
00:24:42
about it this way this this this
00:24:43
schematic here in some resistance
00:24:45
reduces peripheral glucose uptake. And
00:24:49
it's it leaves more for the brain which
00:24:51
does not require insulin ports uptake
00:24:54
right and it's one of the main non
00:24:55
insulin dependent users of good goes to
00:24:58
can think of insulin is having this
00:24:59
function as it you know of course that
00:25:01
leads to diabetes we know that but from
00:25:03
a functional perspective it's really
00:25:04
about the body re prioritising where
00:25:07
it's using energy and moving it from
00:25:09
less final functions to more vital
00:25:11
functions like the bright and that that
00:25:12
is what it's function as this page here
00:25:16
is this is really where I think we're
00:25:18
some the action somewhere evolution
00:25:20
must've shape these responses because
00:25:23
this is where sixty six percent of our
00:25:24
income has to go to that mortgage that
00:25:26
we have to meet each month okay now
00:25:30
we're not gonna have a lot to say about
00:25:31
this "'cause" this is outside my area
00:25:33
when I have a few speculations at the
00:25:34
end implications for the role of
00:25:37
nutrition in cognitive development and
00:25:40
there's not a lot done on this topic
00:25:43
and here we see the brain broad
00:25:45
philosophy car. So very fast bring
00:25:48
growth here slowing down. And and so
00:25:51
naturally a lot of the focus has been
00:25:53
on this period of rapid range of K
00:25:57
because it's not at the point at which
00:25:58
the green is growing fastest but it's
00:26:00
also period we have weeding infectious
00:26:02
disease. Growth faltering right it's
00:26:05
also critical period body growths
00:26:07
substantial growth most outstanding as
00:26:10
occurred by two three years of age is a
00:26:12
lot of action here turns an exceptional
00:26:14
stressed and much of the work on the
00:26:17
role of malnutrition in cognitive
00:26:19
development has focused on this period
00:26:21
and it's found pretty strong evidence
00:26:23
in favour and not gonna deny that but I
00:26:26
think that our work points to another
00:26:28
potentially interesting period okay
00:26:30
this is a period when we look the
00:26:32
growth of the brain is mostly ceased
00:26:34
least you know towards the end here.
00:26:36
And yet you have this P can bring on
00:26:38
objects. And so in what ways might
00:26:41
nutritional stress impact some of the
00:26:43
processes that are being laid down
00:26:44
during this period a the studies that I
00:26:47
seen and I I'm I'm not an expert in
00:26:49
this literature most of them find
00:26:51
strong evidence for here not as much
00:26:53
here. But a lot of those studies
00:26:55
actually just focus on here so I think
00:26:56
that there's there's enough of a
00:26:58
question here that maybe some
00:26:59
additional attention needs to be
00:27:01
focused on this. And it's a very simple
00:27:04
kind of started hypothesis own here
00:27:07
again I reassured you describe it shows
00:27:09
you that what's what's developing at
00:27:10
this age or higher cognitive functions
00:27:12
right so things like executive function
00:27:14
might imagine that those would be
00:27:17
impacted by nutritional stress during
00:27:19
this period so here's to very simple
00:27:22
and not mutually exclusive productions
00:27:24
the crack or severe energy stress
00:27:27
including infections during the bring
00:27:29
energetic speak are gonna be too long
00:27:31
term deficits in the higher cognitive
00:27:33
functions they're developing most
00:27:34
rapidly at that age. And or
00:27:37
developmental delays that work to
00:27:39
protect those kind of outcomes but
00:27:40
possibly what are the ramifications
00:27:42
social ramifications. So these are just
00:27:45
a couple of reasons that we need to
00:27:48
take the brain and it's energetic
00:27:49
costing development very seriously I
00:27:51
think it has implications for a whole
00:27:52
range of different questions with that
00:27:55
I will acknowledge my co authors and
00:27:57
funding agencies and thank you for your
Conference Program
Introduction to the 12th Nestlé International Nutrition Symposium
Thomas Beck, NRC Director
Oct. 22, 2015 · 8:57 a.m.
790 views
Introduction to Session I - Cognitive & Brain Development
Susan Gasser, Friedrich Miescher Institute, Basel, Switzerland
Oct. 22, 2015 · 9:04 a.m.
164 views
The development of a healthy brain
Michael Gazzaniga, University of California, Santa Barbara, USA
Oct. 22, 2015 · 9:16 a.m.
398 views
Q&A - The development of a healthy brain
Michael Gazzaniga, University of California, Santa Barbara, USA
Oct. 22, 2015 · 9:56 a.m.
Early influences on brain development and epigenetics
Stephen G. Matthews, University of Toronto, Canada
Oct. 22, 2015 · 10:49 a.m.
154 views
Q&A - Early influences on brain development and epigenetics
Stephen G. Matthews, University of Toronto, Canada
Oct. 22, 2015 · 11:29 a.m.
Building the physiology of thought
Rebecca Saxe, Massachusetts Institute of Technology, Cambridge, USA
Oct. 22, 2015 · 11:38 a.m.
226 views
Q&A - Building the physiology of thought
Rebecca Saxe, Massachusetts Institute of Technology, Cambridge, USA
Oct. 22, 2015 · 12:10 p.m.
Introduction to Session II - Cognitive Decline
Kathinka Evers
Oct. 22, 2015 · 2:02 p.m.
Brain health & brain diseases - future perspectives
Richard Frackowiak, CHUV University Hospital, Lausanne, Switzerland
Oct. 22, 2015 · 2:11 p.m.
120 views
Alzheimer's disease: genome-wide clues for novel therapies
Rudolph E. Tanzi, Massachusetts General Hospital, Charlestown, USA
Oct. 22, 2015 · 3:15 p.m.
Q&A - Alzheimer's disease: genome-wide clues for novel therapies
Rudolph E. Tanzi, Massachusetts General Hospital, Charlestown, USA
Oct. 22, 2015 · 3:59 p.m.
Immunometabolic regulators of age-related inflammation
Vishwa D. Dixit, Yale School of Medicine, New Haven, USA
Oct. 22, 2015 · 4:21 p.m.
160 views
Q&A - Immunometabolic regulators of age-related inflammation
Vishwa D. Dixit, Yale School of Medicine, New Haven, USA
Oct. 22, 2015 · 4:59 p.m.
Introduction to Session III - Nutrition & Cognitive Development
Pierre Magistretti, KAUST, Thuwal, Saudi Arabia and EPFL, Lausanne, Switzerland
Oct. 23, 2015 · 9 a.m.
Energy metabolism in long-term memory formation and enhancement
Cristina M. Alberini, The Center for Neural Science, New York University, USA
Oct. 23, 2015 · 9:16 a.m.
413 views
Q&A - Energy metabolism in long-term memory formation and enhancement
Cristina M. Alberini, The Center for Neural Science, New York University, USA
Oct. 23, 2015 · 9:53 a.m.
Building the costly human brain: implications for the evolution of slow childhood growth and the origins of diabetes
Christopher Kuzawa, Northwestern University, Evanston, USA
Oct. 23, 2015 · 10:29 a.m.
Q&A - Building the costly human brain: implications for the evolution of slow childhood growth and the origins of diabetes
Christopher Kuzawa, Northwestern University, Evanston, USA
Oct. 23, 2015 · 10:57 a.m.
Nutrition, growth and the developing brain
Prof. Maureen Black, University of Maryland, School of Medicine, Baltimore, USA
Oct. 23, 2015 · 11:09 a.m.
152 views
Q&A - Nutrition, growth and the developing brain
Prof. Maureen Black, University of Maryland, School of Medicine, Baltimore, USA
Oct. 23, 2015 · 11:49 a.m.
Introduction to Session IV - Decline & Nutritional Intervention
Tamas Bartfai, The Scripps Research Institute, La Jolla, USA
Oct. 23, 2015 · 12:48 p.m.
179 views
On multi-domain approaches for prevention trials
Miia Kivipelto, Karolinska Institutet, Stockholm, Sweden
Oct. 23, 2015 · 1:04 p.m.
218 views
Q&A - On multi-domain approaches for prevention trials
Miia Kivipelto, MD, PhD, Karolinska Institutet
Oct. 23, 2015 · 1:39 p.m.
Methodological challenges in Alzheimer clinical development
Lon S. Schneider, Keck School of Medicine of USC, Los Angeles, USA
Oct. 23, 2015 · 1:49 p.m.
124 views
Q&A - Methodological challenges in Alzheimer clinical development
Lon S. Schneider, Keck School of Medicine of USC, Los Angeles, USA
Oct. 23, 2015 · 2:32 p.m.
We are what we remember: memory and age related memory disorders
Eric R. Kandel, Columbia University, New York, USA
Oct. 23, 2015 · 3:03 p.m.
230 views
Concluding Remarks
Stefan Catsicas, Chief Technology Officer, Nestlé SA
Oct. 23, 2015 · 3:50 p.m.
168 views
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