Baby Brains: Unlocking Our Humanity | Rebecca Saxe | TEDxCambridge


Translator: Xin Yue Koh
Reviewer: Laura Pasquale When you look at this picture,
what do you see? This picture is an MRI image
of a mother and her child that I made in my lab at MIT. You might see it as sweet and touching,
a kind of modern Madonna, an image of universal love. We can’t see clothes or hairstyles
or even skin colour. From what we do see,
the biology in the brains, this could be any mother and child,
or even father and child, at any time and place in history, having an experience
that any human could recognise. Or you might see it as disturbing, a reminder that our human bodies are much too fragile
as houses for ourselves. MRIs are usually medical images
and often bad news. Each white spot in that picture
is a blood vessel that could clog. Each tiny fold of those brains
could harbour a tumour. The baby’s brain maybe
looks particularly vulnerable, pressed against the soft,
thin shell of its skull. I see those things, universal emotions,
frightening fragility, but I also see one of the most amazing
transformations in biology and one of the hardest
problems for science. Where do we come from? Less than a year earlier, that baby’s brain was
a tiny clump of cells, basically similar to the clump of cells
that would become the brain of a mouse or a fly or a sea slug. And then some combination of biological
machinery and environmental experience taught those cells how to develop
into a human baby’s brain and then a human adult brain with all the special human capacities
for language and empathy and morality. So I suggest that if we want
to understand the human mind, we have to start at the beginning
and study the brains of babies because the answers could
unlock so many mysteries, like: how much of what we see and think
and feel about our world is universal, shared with all human beings, and how much is unique,
specific to each one of us? How do learning and experience
change who we are? By studying the brains of babies, we could literally see
the beginnings of ourselves. And those are big, abstract,
even philosophical questions, but this research would have
concrete payoffs too, in understanding the brain’s
vulnerability and its resilience. Probably everyone in this room
has loved someone with brain damage. I do. My grandmother has Alzheimer’s disease. My grandfather had Parkinson’s disease. My father had a stroke. In an adult, most brain
damage is permanent, but baby brains are more adaptable and can compensate
for many kinds of damage. And if we knew how that worked and could bring some
of that adaptability to the adults, imagine the difference
we could make in our lives. On the other hand,
babies’ brains are vulnerable and might contain
the signs of later problems, like autism or dyslexia or depression. And we’d like to be able
to catch those signs early and do something before
the child has to fail or suffer. Those goals are part of
why I am a scientist, part of why I keep going
to work in the morning. I study human brain development because I want to understand
how the human mind is built and maybe be able to help
fix it when it’s broken. That’s the distant horizon
but it could be very distant. We still really know almost nothing
about human baby brains, and that’s because studying
the brains of babies is really hard. Now, human babies are a hard population
to study at the best of times. Compared to human adults,
they don’t follow instructions, and they burp and poo
and fall asleep during your experiments. (Laughter) Compared to mice and flies and sea slugs,
they are hard to breed. (Laughter) Studying the brain adds extra challenges, and that’s because the best tool to study
human brain function is an fMRI. An fMRI is a recording of brain function; it lets us watch blood
flow through the brain, bringing the oxygen that it needs to work. So while you’re sitting here, oxygenated blood is flowing
through your brain, and it’s going to different places
if you’re listening to what I’m saying or looking at my face or just daydreaming
about what you did last night. fMRI is a neuroscientist’s
dream come true. Just 20 years ago, before fMRI, looking inside someone’s brain
was dangerous and rare. It happened during surgery,
as a result of injury, or after death. And the picture that it gave us of human
brain function was like a blurry snapshot. When I started trying
to become a scientist, fMRI had just become available,
and we felt like suddenly we could make gorgeous,
high-definition movies of anyone’s brain doing basically anything,
like language and empathy and morality. That’s the research I do in adults. And for the last eight years,
I’ve been gearing up to use the same tool
to study the brains of babies. Eight years is by far the longest I’ve ever spent working
on a single experiment, and that’s because using fMRI and babies
brings a bunch of extra challenges. First of all, the baby needs to be still. Even though we’re using
a cutting-edge machine, it can feel like we’re trying
to take a picture in the 19th century. If you move at all
while we’re taking the picture, all we see is a blur. To give you a sense of this,
for any parent in the room, think about a family photo shoot, trying to get your 6-month-old baby
to smile for the perfect photo. Now imagine she had
to hold that exact smile, moving less than a millimetre,
for eight minutes. (Laughter) Second, the baby needs to be awake. The whole point of this experiment is that we’re trying to study
how the brain experiences the world, so we need to give the baby
an experience of the world whilst shoved inside
the tube of an MRI machine. So we do that by showing them movies of the kinds of things
they like to look at anyway in their everyday lives, like moving around
in their neighbourhoods or the smiling faces of their friends. And then third, if you’ve ever
been in an MRI machine, you know it can be loud and uncomfortable. And so we needed to make
some technical innovation so that it would be quiet
and comfortable for the babies. So for six years,
progress was steady but slow. And that was okay
because conventional wisdom said this whole thing was doomed anyway,
fMRI-ing babies is obviously impossible. And so we might have kept fiddling
with the technical details forever. But then in 2013, life gave us
a golden opportunity and a hard deadline. I was pregnant with my first child. My son Arthur was born in September, so the experiment
had to be ready by October. (Laughter) And finally, here was our chance. All the hard work and planning and experimental design
of the past six years would be put to the test
of an actual baby’s brain. An actual baby who had to be comfortable
and happy and still and awake. So I jumped up and squished myself up
into the MRI machine with him, started singing in his ears,
stroking his face. And we started the machine,
we started playing the movies. (Laughter) And with my face squished
right up against Arthur’s, I watched him lie back,
relax, and fall asleep. (Laughter) A few days later, we tried again
and the movies wouldn’t play. The next time, the MRI
machine wouldn’t turn on. The time after that, Arthur wiggled
through the entire session. And day after day, as I lay squished in an MRI machine,
cuddling my newborn son, I would think, ‘No wonder we don’t know
anything about human baby brains (Laughter) because this is impossible!’ (Laughter) Okay, so I’m telling you this story because it encapsulates
what it means to me to be a scientist. We have this cultural image of a scientist
that we got in high school science class, mechanically applying some
pre-determined ‘scientific method’ to a technical problem that seems
pretty far removed from human experience. You’d think that the fun part
was all at the end, when you find the answers,
when you announce the discoveries. And discoveries are great, and the distant horizon
is really important – the desire to understand and to help – but I am a scientist;
not because of the answers, but because of the questions,
because of the process. And that doesn’t feel anything like
a high school science class. It feels more like I’m guiding
an expedition through the dense woods, and somewhere there’s
a mountain with a view of the horizon, but right now all I can see is my feet. And with each tiny step,
I’m thinking, ‘Is this a path?’ I’m addicted to that process of science,
which is creative and collaborative and passionate and personal and slow
and hard and usually doesn’t work. And that’s because we’re trying to find those tiny, rare places
at the edge of our ignorance, where progress is just barely possible. And we’re still trying to figure out
what questions to ask and how to ask them, let alone what the answers might mean. So tonight I want to give you
this different picture of a scientist, squished inside the tube
of an MRI machine with a tiny baby, singing ‘The Wheels On The Bus’
over and over again and counting the beeps on the MRI machine
to check if we’re getting data, changing experimental protocols
while changing diapers. (Laughter) Deciding to quit,
deciding that it’s impossible. And then, a few days later,
getting so curious because this baby is developing his brain,
and imagine if we knew how, and not being able to resist trying again. So, one day in January 2014,
the experiment worked for the first time, and we got the first glimpse
of Arthur’s brain in action. That was two years ago. And since then, 19 more babies
have participated in that experiment, including my second son, Percy. And these are the first clear
fMRI pictures ever made of babies’ brains looking
at faces and scenes. In these images we can see that babies’ brains are more mature
than we ever expected, though we can also see room
for learning and change. Almost everything in these pictures we couldn’t have predicted,
even this time last year. Finding such clear pictures
was so exciting, it took my breath away. But this research programme
is actually just beginning, and I’m even more excited
about the questions we can ask now. Like how much of what we see
in these pictures is universal, shared by all human babies, and how much is specific
and unique to each individual child? How will learning and experience
change those pictures? Is there something we could see
in a picture like this that would be the earliest sign
of a problem like autism or dyslexia or depression? Can we use this research to understand why human babies are so resilient
to some kinds of trauma and so vulnerable to others? Those are big, important
scientific questions, but to me they are personal ones, too. Because one of those unique and changing and vulnerable and resilient
brains is my son[‘s]. So when you look at this picture now, I hope you see a little
more of what I see: sweet love, dangerous fragility,
but also the amazing window that scientific progress is opening
on the beginnings of ourselves. And maybe also a challenge
to our iconic cultural images of mothers on the one hand
and scientists on the other, because this is a picture of me,
being a scientist and a mother, curled up inside the MRI tube
with my newborn son. Thank you. (Applause)

4 Comments

Add a Comment

Your email address will not be published. Required fields are marked *