What we'll learn about the brain in the next century | Sam Rodriques

Translator: Silvia Miguélez Reviewer: Servizo de Normalización Lingüística

I want to tell you guys something about neuroscience.

Quero contarvos algo sobre neurociencia.

Son físico de formación.

I'm a physicist by training.

About three years ago, I left physics

Hai uns tres anos deixei a física

to come and try to understand how the brain works.

para comprender como funciona o cerebro.

And this is what I found.

E isto foi o que descubrín:

Lots of people are working on depression.

moita xente está a estudar a depresión.

And that's really good,

Iso está moi ben,

depression is something that we really want to understand.

xa que é algo que queremos entender.

Así é como se fai:

Here's how you do it:

you take a jar and you fill it up, about halfway, with water.

collemos un frasco e enchémolo con auga ata a metade.

And then you take a mouse, and you put the mouse in the jar, OK?

Despois collemos un rato e poñémolo no frasco, si?

And the mouse swims around for a little while

E o rato nada un pouco,

and then at some point, the mouse gets tired

ata que cansa

and decides to stop swimming.

e decide deixar de nadar.

And when it stops swimming, that's depression.

Cando deixa de nadar, iso é depresión.

OK?

De acordo?

And I'm from theoretical physics,

Son da física teórica,

so I'm used to people making very sophisticated mathematical models

polo que estou afeito a que se fagan modelos matemáticos moi sofisticados

to precisely describe physical phenomena,

para describir os fenómenos físicos dun xeito preciso.

so when I saw that this is the model for depression,

Cando vin que este é o modelo para a depresión,

I though to myself, "Oh my God, we have a lot of work to do."

pensei: “Meu Deus, temos moito traballo que facer.”

(Laughter)

(Risas)

But this is a kind of general problem in neuroscience.

Pero este é un problema xeral na neurociencia.

So for example, take emotion.

Por exemplo, pensade nas emocións.

Lots of people want to understand emotion.

Moita xente quere entender as emocións.

But you can't study emotion in mice or monkeys

Pero non se poden estudar en ratos ou monos,

because you can't ask them

porque non podemos preguntarlles como se senten ou que senten.

how they're feeling or what they're experiencing.

Por iso, os que queren entender as emocións

So instead, people who want to understand emotion,

typically end up studying what's called motivated behavior,

adoitan estudar o que chamamos comportamento motivado,

which is code for "what the mouse does when it really, really wants cheese."

noutras palabras, que é o que fai o rato cando realmente quere queixo.

OK, I could go on and on.

E podería seguir.

I mean, the point is, the NIH spends about 5.5 billion dollars a year

O tema é que o Instituto de Saúde dos EE. UU.

gasta uns 5500 millóns de dólares ao ano

on neuroscience research.

na investigación en neurociencia.

And yet there have been almost no significant improvements in outcomes

Aínda así, case non houbo melloras significativas nos resultados

for patients with brain diseases in the past 40 years.

para pacientes con enfermidades cerebrais nos últimos 40 anos.

Creo que moito diso débese basicamente ao feito

And I think a lot of that is basically due to the fact

that mice might be OK as a model for cancer or diabetes,

de que os ratos poden ser un bo modelo para o cancro ou a diabetes,

but the mouse brain is just not sophisticated enough

pero o seu cerebro non é sofisticado dabondo

to reproduce human psychology or human brain disease.

para reproducir a psicoloxía humana ou a enfermidade cerebral humana.

OK?

De acordo?

So if the mouse models are so bad, why are we still using them?

Entón, se os modelos de rato son tan malos, por que seguimos usándoos?

Well, it basically boils down to this:

O motivo é o seguinte:

the brain is made up of neurons

o cerebro está formado por neuronas,

which are these little cells that send electrical signals to each other.

que son pequenas células que se envían sinais eléctricos entre si.

If you want to understand how the brain works,

Para entender como funciona o cerebro,

you have to be able to measure the electrical activity of these neurons.

temos que ser capaces de medir a actividade eléctrica destas neuronas.

But to do that, you have to get really close to the neurons

Pero, para facelo, hai que achegarse moito ás neuronas

with some kind of electrical recording device or a microscope.

cun dispositivo de rexistro eléctrico ou cun microscopio.

And so you can do that in mice and you can do it in monkeys,

Podemos facelo en ratos e en monos,

because you can physically put things into their brain

porque é posible poñerlles cousas no cerebro,

but for some reason we still can't do that in humans, OK?

pero por algunha razón seguimos sen poder facelo en humanos.

So instead, we've invented all these proxies.

Polo tanto, inventamos todos estes substitutos.

So the most popular one is probably this,

Probablemente o máis popular sexa este:

functional MRI, fMRI,

a resonancia magnética funcional, ou RMf,

which allows you to make these pretty pictures like this,

que nos permite obter imaxes tan bonitas coma esta,

that show which parts of your brain light up

que mostran que rexións se iluminan

when you're engaged in different activities.

cando facemos diferentes actividades.

But this is a proxy.

Pero isto é un substituto.

You're not actually measuring neural activity here.

Non estamos a medir a actividade neuronal.

What you're doing is you're measuring, essentially,

O que estamos a facer é medir

like, blood flow in the brain.

o fluxo sanguíneo no cerebro.

Where there's more blood.

Onde hai máis sangue.

It's actually where there's more oxygen, but you get the idea, OK?

De feito é onde hai máis osíxeno, pero enténdese.

Outra cousa que podemos facer é o seguinte:

The other thing that you can do is you can do this --

electroencephalography -- you can put these electrodes on your head, OK?

un electroencefalograma.

Poñemos estes eléctrodos na cabeza para medir as ondas cerebrais.

And then you can measure your brain waves.

And here, you're actually measuring electrical activity.

E aquí estamos a medir a actividade eléctrica,

But you're not measuring the activity of neurons.

o que non medimos é a actividade neuronal.

You're measuring these electrical currents,

Estamos a medir as correntes eléctricas,

que percorren o cerebro dun lado cara ao outro.

sloshing back and forth in your brain.

So the point is just that these technologies that we have

A cuestión é que estas tecnoloxías que temos

are really measuring the wrong thing.

están a medir a información incorrecta.

Because, for most of the diseases that we want to understand --

para a maioría das enfermidades que queremos entender.

O exemplo clásico é o párkinson.

like, Parkinson's is the classic example.

In Parkinson's, there's one particular kind of neuron deep in your brain

No párkinson, hai un tipo de neurona no cerebro

that is responsible for the disease,

que é responsable da enfermidade,

and these technologies just don't have the resolution that you need

e estas tecnoloxías simplemente non teñen a resolución necesaria

para observala.

to get at that.

And so that's why we're still stuck with the animals.

Por iso é polo que seguimos a traballar cos animais.

Not that anyone wants to be studying depression

Non é que alguén queira estudar a depresión

by putting mice into jars, right?

poñendo ratos en frascos, certo?

It's just that there's this pervasive sense that it's not possible

É só que hai unha idea xeneralizada de que non é posible

to look at the activity of neurons in healthy humans.

observar a actividade neuronal en humanos sans.

So here's what I want to do.

Isto é o que quero facer:

I want to take you into the future.

quero levarvos ao futuro

To have a look at one way in which I think it could potentially be possible.

para ver como podería chegar a ser posible.

And I want to preface this by saying, I don't have all the details.

Comezo dicindo que non teño todos os detalles,

So I'm just going to provide you with a kind of outline.

así que vos vou dar unha especie de esquema.

But we're going to go the year 2100.

Imos viaxar ao ano 2100.

Now what does the year 2100 look like?

Como será o ano 2100?

Well, to start with, the climate is a bit warmer that what you're used to.

Para comezar, o clima é máis cálido do que estamos afeitos.

(Laughter)

(Risas)

And that robotic vacuum cleaner that you know and love

E ese aspirador robótico que coñecemos e adoramos

went through a few generations,

pasou por algunhas xeracións,

and the improvements were not always so good.

e as melloras non sempre foron boas.

(Laughter)

(Risas)

It was not always for the better.

Non sempre foi para mellor.

But actually, in the year 2100 most things are surprisingly recognizable.

Pero no ano 2100 a maioría das cousas aínda son recoñecibles.

It's just the brain is totally different.

Só o cerebro é completamente diferente.

For example, in the year 2100,

Por exemplo, no 2100

we understand the root causes of Alzheimer's.

entendemos as causas reais do alzhéimer,

So we can deliver targeted genetic therapies or drugs

e podemos administrar terapias xenéticas ou fármacos dirixidos

to stop the degenerative process before it begins.

para deter o proceso dexenerativo antes de que comece.

So how did we do it?

Como o fixemos?

Well, there were essentially three steps.

Houbo esencialmente tres pasos.

The first step was that we had to figure out

O primeiro paso foi que tiñamos que atopar un xeito

some way to get electrical connections through the skull

de meter conexións eléctricas polo cranio

so we could measure the electrical activity of neurons.

para medir a actividade eléctrica das neuronas.

And not only that, it had to be easy and risk-free.

Ademais, tiña que ser fácil e sen risco ningún,

Something that basically anyone would be OK with,

algo co que calquera puidese estar de acordo,

like getting a piercing.

como facerse un piercing.

Because back in 2017,

Porque, no 2017,

the only way that we knew of to get through the skull

a única forma coñecida de atravesar o cranio

was to drill these holes the size of quarters.

era perforar uns buratos do tamaño de moedas.

Nunca deixariades vos fixesen iso.

You would never let someone do that to you.

So in the 2020s,

Na década de 2020,

people began to experiment -- rather than drilling these gigantic holes,

a xente empezou a experimentar: en vez de perforar buratos enormes,

drilling microscopic holes, no thicker than a piece of hair.

facían buratos microscópicos, non maiores que un cabelo.

And the idea here was really for diagnosis --

A idea era axudar ao diagnóstico.

there are lots of times in the diagnosis of brain disorders

Moitas veces no diagnóstico de trastornos cerebrais

when you would like to be able to look at the neural activity beneath the skull

gustaríanos poder observar a actividade neuronal baixo o cranio.

and being able to drill these microscopic holes

Se puidésemos perforar estes buratos microscópicos

would make that much easier for the patient.

sería moito máis fácil para o paciente.

In the end, it would be like getting a shot.

Ao final, sería como recibir unha inxección.

You just go in and you sit down

Só entras e sentas,

and there's a thing that comes down on your head,

algo baixa sobre a túa cabeza,

hai unha picada momentánea, e xa está,

and a momentary sting and then it's done,

and you can go back about your day.

e podes seguir co teu día normal.

So we're eventually able to do it

Finalmente puidemos facelo

using lasers to drill the holes.

usando láseres para perforar os buratos.

And with the lasers, it was fast and extremely reliable,

E cos láseres foi rápido e moi fiable,

you couldn't even tell the holes were there,

nin sequera notariades os buratos,

any more than you could tell that one of your hairs was missing.

como non nos decatamos da falta dun só cabelo.

And I know it might sound crazy, using lasers to drill holes in your skull,

Sei que pode parecer tolo usar láseres para facer buratos no cranio,

but back in 2017,

pero, no ano 2017,

people were OK with surgeons shooting lasers into their eyes

á xente parecíalle ben que os cirurxiáns usaran láseres nos seus ollos

para cirurxía correctiva.

for corrective surgery

So when you're already here, it's not that big of a step.

Tendo isto en conta, xa non foi un paso tan grande.

OK?

De acordo?

So the next step, that happened in the 2030s,

O paso seguinte, que ocorreu na década de 2030,

was that it's not just about getting through the skull.

foi que non chegaba con atravesar o cranio.

To measure the activity of neurons,

Para medir a actividade neuronal,

you have to actually make it into the brain tissue itself.

hai que atravesar o tecido cerebral.

And the risk, whenever you put something into the brain tissue,

O risco que hai cando metemos algo nese tecido

é basicamente que haxa un ictus.

is essentially that of stroke.

That you would hit a blood vessel and burst it,

Golpear un vaso sanguíneo e rompelo

causaría un ictus.

and that causes a stroke.

So, by the mid 2030s, we had invented these flexible probes

A mediados da década de 2030 inventamos estas sondas flexibles

that were capable of going around blood vessels,

que podían percorrer os vasos sanguíneos

rather than through them.

en vez de atravesalos.

And thus, we could put huge batteries of these probes

Así puidemos poñer moitas destas sondas

into the brains of patients

nos cerebros dos pacientes

and record from thousands of their neurons without any risk to them.

e gravar miles das súas neuronas sen risco ningún.

And what we discovered, sort of to our surprise,

E o que descubrimos, para a nosa sorpresa,

is that the neurons that we could identify

é que as neuronas que puidemos identificar

were not responding to things like ideas or emotion,

non respondían a cousas como ideas ou emocións,

which was what we had expected.

que era o que esperabamos.

They were mostly responding to things like Jennifer Aniston

Respondían principalmente a cousas como Jennifer Aniston

or Halle Berry

ou Halle Berry

or Justin Trudeau.

ou Justin Trudeau.

I mean --

Quero dicir…

(Laughter)

(Risas)

In hindsight, we shouldn't have been that surprised.

Mirando cara a atrás, non debería sorprendernos.

I mean, what do your neurons spend most of their time thinking about?

É dicir, en que pensan as neuronas a maior parte do tempo?

(Laughter)

(Risas)

But really, the point is that

A cuestión é que esta tecnoloxía

this technology enabled us to begin studying neuroscience in individuals.

permitiunos comezar a estudar neurociencia en individuos.

So much like the transition to genetics, at the single cell level,

Como pasara coa transición da xenética, a nivel dunha soa célula,

we started to study neuroscience, at the single human level.

comezamos a estudar a neurociencia ao nivel dun individuo.

But we weren't quite there yet.

Pero aínda quedaba moito que facer.

Because these technologies

Porque estas tecnoloxías

were still restricted to medical applications,

aínda estaban restrinxidas á súa aplicación médica,

which meant that we were studying sick brains, not healthy brains.

é dicir, que estabamos a estudar cerebros enfermos, non cerebros sans.

Because no matter how safe your technology is,

Por moi segura que sexa a tecnoloxía,

non podemos meter nada no cerebro de alguén

you can't stick something into someone's brain

for research purposes.

con fins de investigación.

They have to want it.

É preciso que eles queiran.

And why would they want it?

E por que quererían?

Because as soon as you have an electrical connection to the brain,

Porque en canto tes unha conexión eléctrica co cerebro,

you can use it to hook the brain up to a computer.

podes usala para conectalo a un ordenador.

Oh, well, you know, the general public was very skeptical at first.

O público en xeral foi moi escéptico ao principio.

I mean, who wants to hook their brain up to their computers?

Quen podería querer conectar o seu cerebro cos ordenadores?

Well just imagine being able to send an email with a thought.

Pois imaxinade poder enviar un correo electrónico cun pensamento.

(Laughter)

(Risas)

Imagine being able to take a picture with your eyes, OK?

Imaxinade poder facer unha foto cos ollos, de acordo?

(Laughter)

(Risas)

Imagine never forgetting anything anymore,

Imaxinade que nunca máis esquecedes nada,

because anything that you choose to remember

porque calquera cousa que escollades lembrar

will be stored permanently on a hard drive somewhere,

se almacena para sempre nun disco duro nalgún lugar,

able to be recalled at will.

e podedes recordala a vontade.

(Laughter)

(Risas)

The line here between crazy and visionary

A liña entre tolo e visionario aquí

was never quite clear.

nunca estivo moi clara.

But the systems were safe.

Pero os sistemas eran seguros.

So when the FDA decided to deregulate these laser-drilling systems, in 2043,

No 2043, cando a FDA decidiu desregular estes sistemas de perforación láser,

commercial demand just exploded.

estoupou a demanda comercial.

People started signing their emails,

A xente comezou a asinar os correos:

"Please excuse any typos.

“Desculpa os erros. Enviado desde o meu cerebro.”

Sent from my brain."

(Laughter)

(Risas)

Commercial systems popped up left and right,

Apareceron por todas partes sistemas comerciais,

offering the latest and greatest in neural interfacing technology.

que ofrecían o último e o mellor en tecnoloxía de interface neuronal.

There were 100 electrodes.

Había 100 eléctrodos.

A thousand electrodes.

Mil eléctrodos.

High bandwidth for only 99.99 a month.

Gran ancho de banda por só 99,99 ao mes.

(Laughter)

(Risas)

Soon, everyone had them.

Pronto todos os tiñan.

And that was the key.

E esa foi a clave.

Because, in the 2050s, if you were a neuroscientist,

Porque como neurocientíficos na década de 2050,

you could have someone come into your lab essentially from off the street.

poderiades facer que alguén entrase ao teu laboratorio desde a mesma rúa

And you could have them engaged in some emotional task

e involucralo nalgunha tarefa emocional

or social behavior or abstract reasoning,

ou comportamento social ou razoamento abstracto,

things you could never study in mice.

cousas que nunca poderiades estudar nos ratos.

And you could record the activity of their neurons

Poderiades rexistrar a súa actividade neuronal

using the interfaces that they already had.

usando as interfaces que xa tiñan.

And then you could also ask them about what they were experiencing.

Tamén poderiades preguntarlles que estaban a experimentar.

Esta relación entre a psicoloxía e a neurociencia,

So this link between psychology and neuroscience

that you could never make in the animals, was suddenly there.

que nunca se puidera facer nos animais, estaba alí de súpeto.

So perhaps the classic example of this

Quizais o exemplo clásico disto

was the discovery of the neural basis for insight.

foi o descubrimento da base neuronal para a comprensión.

That "Aha!" moment, the moment it all comes together, it clicks.

Ese momento do “Claro!”, o momento en que todo encaixa.

And this was discovered by two scientists in 2055,

Dous científicos descubrírono no 2055,

Barry and Late,

Nonera e Sentempo,

who observed, in the dorsal prefrontal cortex,

que observaran, no córtex prefrontal dorsal

how in the brain of someone trying to understand an idea,

do cerebro de alguén que trataba de comprender unha idea

como se reorganizarían as diferentes poboacións de neuronas

how different populations of neurons would reorganize themselves --

you're looking at neural activity here in orange --

—a actividade neuronal sae en laranxa—

until finally their activity aligns in a way that leads to positive feedback.

ata que a súa actividade se aliñase e chegase a unha resposta positiva.

Right there.

Aquí mesmo.

That is understanding.

Iso é comprensión.

So finally, we were able to get at the things that make us human.

Finalmente puidemos chegar ás cousas que nos fan humanos.

And that's what really opened the way to major insights from medicine.

E iso foi o que abriu o camiño a grandes descubrimentos na medicina.

Because, starting in the 2060s,

Porque desde a década de 2060,

with the ability to record the neural activity

ao poder rexistrar a actividade neuronal

in the brains of patients with these different mental diseases,

dos cerebros de pacientes con diferentes enfermidades mentais,

rather than defining the diseases on the basis of their symptoms,

en vez de definir as enfermidades en función dos síntomas,

as we had at the beginning of the century,

como tiñamos feito a comezos de século,

we started to define them

comezamos a definilas

on the basis of the actual pathology that we observed at the neural level.

con base na patoloxía real que observabamos a nivel neuronal.

So for example, in the case of ADHD,

Por exemplo, no caso do TDAH,

we discovered that there are dozens of different diseases,

descubrimos que hai ducias de enfermidades diferentes,

all of which had been called ADHD at the start of the century,

todas elas coñecidas como TDAH a comezos de século,

that actually had nothing to do with each other,

cando, de feito, nada tiñan que ver entre elas;

except that they had similar symptoms.

só tiñan síntomas semellantes.

And they needed to be treated in different ways.

Precisaban tratarse de diferentes xeitos.

So it was kind of incredible, in retrospect,

Era algo incrible, mirando cara atrás,

that at the beginning of the century,

que, a comezos de século,

we had been treating all those different diseases

tratásemos esas enfermidades diferentes co mesmo medicamento.

with the same drug,

O que facíamos era darlle anfetaminas á xente.

just by giving people amphetamine, basically is what we were doing.

Coa esquizofrenia e a depresión pasaba o mesmo.

And schizophrenia and depression are the same way.

So rather than prescribing drugs to people essentially at random,

En lugar de prescribir medicamentos ao azar,

as we had,

como antes,

we learned how to predict which drugs would be most effective

aprendemos a predicir que medicamentos serían máis efectivos

in which patients,

segundo o paciente,

and that just led to this huge improvement in outcomes.

e iso levou a unha enorme mellora nos resultados.

OK, I want to bring you back now to the year 2017.

Agora quero levarvos de volta ao ano 2017.

Some of this may sound satirical or even far fetched.

Algo disto pode soar satírico ou mesmo esaxerado.

And some of it is.

Algunhas partes sono.

I mean, I can't actually see into the future.

Quero dicir, non podo ver o futuro.

I don't actually know

Non sei realmente

if we're going to be drilling hundreds or thousands of microscopic holes

se imos facer centos ou miles de buratos microscópicos nas cabezas

in our heads in 30 years.

dentro de 30 anos.

But what I can tell you

Pero o que podo dicir

is that we're not going to make any progress

é que non imos facer progresos

towards understanding the human brain or human diseases

na comprensión do cerebro humano ou das enfermidades humanas

until we figure out how to get at the electrical activity of neurons

ata que descubramos como chegar á actividade eléctrica das neuronas

in healthy humans.

en humanos sans.

And almost no one is working on figuring out how to do that today.

E case ninguén está intentando descubrir como facelo.

That is the future of neuroscience.

Ese é o futuro da neurociencia.

And I think it's time for neuroscientists to put down the mouse brain

Creo que é hora de que os neurocientíficos descarten o cerebro de rato

and to dedicate the thought and investment necessary

e dediquen o pensamento e o investimento precisos

to understand the human brain and human disease.

a comprender o cerebro humano e as enfermidades humanas.

Thank you.

Grazas.

(Applause)

(Aplausos)