So it's unethical to do an experiment with a healthy,
human, baby brain so for several years scientists have relying on
animal models for example we try to learn
what happens in a mouse or in a monkey and we extrapolate to humans but as I
pointed out the human brain is so different from other species so we need
to understand how the human brain is formed
so here comes this new technology which is a brain organoid in a brain
organoid is just the recapitulation of the human
development inside the lab using stem cells
to grow every single step at these very early stages of neurodevelopment
let's explain what stem cells are so this will make sense
all right stem cells are cells that are immature they don't have
a fate defined yet for example in in you have your skin cells you have
your blood cells you have your brain cells
all these cells have names right now because they already
acquire some kind of identity in the early stages of
uh the embryogenesis you have stem cells that
are not defined yet they are just self-replicating
and they will give rise to progenitor cells that later
will form all the tissues in the body so these cells we call them pluripotent
stem cells because they can form any tissues of the body
so if they're given the right instructions or stimulus they could
become liver or brain right you don't know so
you figured out how to induce them to becoming brain yeah we
are brain makers we develop uh protocols and recipes,
formulas that we can uh add on these stem cells
uh and instruct them or or fool them around to think that they are in the
right environment to become the cell type that we want
and my lab has been optimizing these protocols to create what we call a brain
organoid or a mini brain some people call them
mini brains because they're just a very miniaturized version of the human brain
so last year we learned how to grow these organoids to create functional
neural networks so that's one step ahead so now so now we have to explain what
the neural net the functional network is right a functional network is when
neurons start to talk to each other and in
and form complex uh nets of information
so that's how our beginning of our cognition appears or
or arises in in the early stages of
neurodevelopment um so so the baby doesn't have all those
connections the baby already have them but they are
not mature enough and in the organoid we never seen that
before because we thought that it would be impossible to recreate that
in vitro and a brain organoid has intrinsic
limitations it's not vascularized not all cell types are
there we don't even know if the conditions are the same condition
as uh in uterus so we were quite skeptical
that the networks would appear in this brain organoids
but so science has evolved to the point where we
we could tweak this protocol and make them actually form these networks
so now we open the possibility to study conditions where the brain is intact
but the networks are not for example conditions like autism or schizophrenia
so we don't see a major neuronal flaws or a neurodegeneration
in autism or schizophrenia but the network but the network is defective
so the question is can we use these brain organoids to find
new drugs or eventual gene therapy to help people with this kind of
neurological conditions so understanding normal how it how it works
how it's supposed to work helps you identify what to do in
situations where it didn't work the way we want it to work exactly that's that's
that's how we do it we always compare the disease condition with the
neurotypical that's what we call disease modeling in
a dish so we're doing this right now I remember years ago i met an indian
sitar player and he gave me music to play for my
children and he and I said why shouldn't I listen to it
he said that I never developed the neural connections
to hear all the sounds because those were not made when I was a
baby and when I can make those networks you speak portuguese and the sounds
I have to concentrate very hard to hear all of that but your neural network
was exposed to that and it was reinforced and created so you're now
looking at these kinds of networks that babies
that's how they learn and grow and being able to develop them in a lab
so that's it's just to me amazing yeah uh that that you're able to do that in a
laboratory and I think you now touch on on on
other things which which might um uh be a little bit more complex for example
uh we could use the same technology to make the same human brain um
more plastic or more adaptable or have more synapses
or be more protective against neurodegeneration later in life
would be nice to have a brain that is protected against alzheimer's
yes so we can ask those questions and perhaps finding answers
and um and and some of these answers might require early modulations of these
networks at very early stages in development so
we as a society we have to discuss the ethical implications of those um
alterations you know as as a parent that's a that's
a tough question to think about and in society that
that's a tough question I don't think we'll answer that today
but but it's an important question because
science is about to give us those options right uh and and
sooner rather than later to decide that I'm a pediatric ophthalmologist
we have children of amblyopia that really can't be treated after you get
older because the neuroplasticity is gone
right uh there are brain injuries that we'd love to be able to repair I mean
there's so much that we'd want to be able to do that you could see
you making a difference in