What happens in your brain when you taste food | Camilla Arndal Andersen

Translator: Ivana Korom Reviewer: Krystian Aparta

Translator: Marta GaNov Reviewer: Xusto Rodriguez

Tiven esta interesante experiencia

hai cinco anos.

O meu marido e eu fomos mercar á tenda,

So I had this very interesting experience

como facemos cada dous días,

pero desta vez, atopamos cousas sofisticadas,

five years ago.

estou a falar de comercio xusto, de comida orgánica,

You know, me and my husband, we were out grocery shopping,

as we do every other day,

de café kenyano de orixe única

but this time, we found this fancy,

nas que malgastamos e mercamos.

you know, I'm talking fair-trade, I'm talking organic,

E foi entón cando xa comezou o problema.

I'm talking Kenyan, single-origin coffee

O meu marido considerou que esta mestura de café era superior

that we splurged and got.

ó noso café habitual, moito máis barato,

And that was when the problem started already.

e isto fíxome imaxinar unha vida baseada unicamente nun café sofisticado

You know, my husband, he deemed this coffee blend superior

e no noso orzamento familiar estoupando.

to our regular and much cheaper coffee,

(Risas)

which made me imagine a life based solely on fancy coffee

E o que é peor...

Tamén temía que este investimento sería en balde.

and I saw our household budget explode.

Que non seriamos capaces de percibir esta diferenza despois de todo.

(Laughter)

And worse ...

Por desgraza, especialmente para o meu marido,

I also feared that this investment would be in vain.

That we wouldn't be able to notice this difference after all.

el esqueceu por un intre que estaba casado cunha neurocientífica

especialista en ciencia da alimentación.

Unfortunately, especially for my husband,

(Risas)

Ben?

Así que sen máis preámbulos,

he had momentarily forgotten that he's married to a neuroscientist

simplemente púxeno a proba.

with a specialty in food science.

Definín un experimento

(Laughter)

onde comecei poñendo a cegas ao meu marido.

Alright?

So without further ado,

(Risas)

I mean, I just put him to the test.

Fixen as dúas clases de café

I set up an experiment

e díxenlle que llos serviría

where I first blindfolded my husband.

un de cada vez.

(Laughter)

Then I brewed the two types of coffee

Con total certeza,

o meu marido describiu a primeira cunca de café

and I told him that I would serve them to him

como máis puro e amargo.

one at a time.

É dicir, un café que sería ideal para as mañás

Now, with clear certainty,

coa única finalidade de arrepiar o corpo esperto co seu sabor alarmante.

my husband, he described the first cup of coffee

as more raw and bitter.

(Risas)

You know, a coffee that would be ideal for the mornings

A segunda cunca de café, pola súa banda,

with the sole purpose of terrorizing the body awake by its alarming taste.

era tan afroitado como delicioso.

(Laughter)

É dicir, un café do que un pode gozar no serán e relaxarse.

The second cup of coffee, on the other hand,

was both fruity and delightful.

O que non sabía o meu marido, pola contra,

You know, coffee that one can enjoy in the evening and relax.

é que non lle dera realmente as dúas clases de café.

Déralle a mesma cunca de café dúas veces.

Little did my husband know, however,

(Risas)

that I hadn't actually given him the two types of coffee.

E obviamente, non foi esta cunca de café

I had given him the exact same cup of coffee twice.

a que de súpeto cambiou de horrible a fantástica.

(Laughter)

Non, a diferenza de sabor foi produto da propia mente do meu marido.

And obviously, it wasn't this one cup of coffee

O seu prexuízo a favor do café sofisticado

that had suddenly gone from horrible to fantastic.

fíxolle experimentar diferenzas no sabor que simplemente non había.

No, this taste difference was a product of my husband's own mind.

Of his bias in favor of the fancy coffee

Así que, perfecto, salvamos o noso presuposto familiar

that made him experience taste differences that just weren't there.

e rematamos cunha boa gargallada,

especialmente eu.

(Risas)

Alright, so, having saved our household budget,

Entón comecei a preguntarme como puido ser que percibiramos

dúas respostas tan diferentes dunha sinxela cunca de café.

and finishing on a very good laugh,

me especially --

Por que faría o meu marido unha afirmación tan ousada

(Laughter)

I then started wondering just how we could have received

co risco de ser ridiculizado publicamente o resto da súa vida?

two such different responses from a single cup of coffee.

Why would my husband make such a bold statement

(Risas)

A resposta sorprendente é que ti farías o mesmo.

at the risk of being publicly mocked for the rest of his life?

E este é o maior desafío no meu ámbito científico,

(Laughter)

valorar o que é realidade tras estas respostas

The striking answer is that I think you would have done the same.

que recibimos.

Porque...como imos facer comida máis saborosa

And that's the biggest challenge in my field of science,

se non podemos confiar no que na xente di que lle gusta?

assessing what's reality behind these answers

that we receive.

Because how are we going to make food tastier

Para poder entendelo, primeiro botémoslle unha ollada a como percibimos a comida.

if we cannot rely on what people actually say they like?

Cando bebo unha cunca de café,

detecto esta cunca de café mediante receptores no meu corpo,

To understand, let's first have a look at how we actually sense food.

unha información que despois se traduce en neuronas activadas no meu cerebro.

When I drink a cup of coffee,

I detect this cup of coffee by receptors on my body,

As lonxitudes de onda da luz convértense en cores.

As moléculas do líquido son detectadas polos receptores na miña boca,

information which is then turned into activated neurons in my brain.

e clasificadas como un dos cinco sabores básicos:

Wavelengths of light are converted to colors.

salgado, acedo, amargo, doce e umami.

Molecules in the liquid are detected by receptors in my mouth,

and categorized as one of five basic tastes.

As moléculas no aire son detectadas polos receptores do meu nariz

That's salty, sour, bitter, sweet and umami.

e convertidas en olores.

E igual para o tacto, para a temperatura, para o son e o demais.

Molecules in the air are detected by receptors in my nose

Toda esta información é detectada polos meus receptores

and converted to odors.

And ditto for touch, for temperature, for sound and more.

e convertida en sinais entre neuronas no meu cerebro.

Unha información que despois é entretecida e integrada,

All this information is detected by my receptors

and converted into signals between neurons in my brain.

e así o meu cerebro recoñece que si,

que tomei unha cunca de café, e si, gustoume.

Information which is then woven together and integrated,

so that my brain recognizes

E só entón,

that yes, I just had a cup of coffee, and yes, I liked it.

despois de toda esta adaptación neuronal,

si experimentamos conscientemente esta cunca de café.

And only then,

Aquí é onde agora cometemos un erro conceptual moi común.

after all this neuron heavy lifting,

do we consciously experience this cup of coffee.

A xente adoita crer que o que experimentamos de maneira consciente

And this is now where we have a very common misconception.

debe ser un reflexo absolutamente certo da realidade.

Pero como acabades de escoitar,

People tend to think that what we experience consciously

hai moitas etapas de interpretación neuronal

must then be an absolute true reflection of reality.

entre o obxecto físico e a experiencia consciente del.

But as you just heard,

O que significa que, ás veces, esta experiencia consciente

there are many stages of neural interpretation

non está a reflectir esa realidade en absoluto.

in between the physical item and the conscious experience of it.

Como o que lle pasou ó meu marido.

Which means that sometimes,

Isto pasa porque os estímulos físicos poden ser tan débiles

this conscious experience is not really reflecting that reality at all.

que sinxelamente non poden atravesar a barreira para entrar na nosa consciencia

Like what happened to my husband.

That's because some physical stimuli may just be so weak

en tanto que a información que resulta

pode torcerse no seu camiño ata alí polos nosos prexuízos ocultos.

that they just can't break that barrier to enter our conscious mind,

E a xente ten moitos prexuízos.

while the information that does

may get twisted on its way there by our hidden biases.

Si, se vós estades agora mesmo aí sentados, pensando...

And people, they have a lot of biases.

que probablemente o fariades mellor que o meu marido,

que probablemente dariades apreciado eses cafés correctamente,

Yes, if you're sitting there right now, thinking ...

entón estades realmente sufrindo un prexuízo.

you could probably have done better than my husband,

Un prexuízo chamado nesgo de punto cego.

you could probably have assessed those coffees correctly,

A nosa tendencia a vernos con menos nesgo ca outras persoas.

then you're actually suffering from a bias.

(Risas)

A bias called the bias blind spot.

E si, mesmo podemos ter prexuízos

Our tendency to see ourselves as less biased than other people.

sobre prexuízos dos que temos prexuízo.

(Risas)

Non estou a facer isto máis doado.

(Laughter)

Un nesgo que coñecemos na industria alimentaria é o de cortesía.

And yeah, we can even be biased

about the biases that we're biased about.

(Laughter)

Not trying to make this any easier.

É un nesgo polo cal damos unha opinión

que se considera socialmente aceptable,

A bias that we know in the food industry is the courtesy bias.

pero que non é realmente a nosa opinión, de acordo?

This is a bias where we give an opinion

Como investigadora sobre alimentación, isto ponme a proba,

which is considered socially acceptable,

porque cando a xente di que lle gusta o meu novo batido baixo en azucre,

but it's certainly not our own opinion, right?

gústalle realmente?

And I'm challenged by this as a food researcher,

(Risas)

Ou están a dicir que lles gusta

because when people say they like my new sugar-reduced milkshake,

porque saben que os estou escoitando e queren compracerme?

do they now?

Ou quizais soamente para que me parezan en forma e saudables.

(Laughter)

Or are they saying they like it

because they know I'm listening and they want to please me?

Non o sabería dicir.

Pero o que é peor, nin eles saberían.

Or maybe they just to seem fit and healthy in my ears.

Mesmo avaliadores de alimentos adestrados,

I wouldn't know.

e persoas que foron expresamente formadas

But worse, they wouldn't even know themselves.

para desenmarañar o sentido do olfacto e do gusto,

aínda poden estar nesgados para avaliar produtos máis doces

Even trained food assessors,

and that's people who have been explicitly taught

se conteñen vainilla.

to disentangle the sense of smell and the sense of taste,

Por que?

Ben, non é realmente porque a vainilla saiba doce.

may still be biased to evaluate products sweeter

if they contain vanilla.

É porque ata estes profesionais son humanos,

Why?

Well, it's certainly not because vanilla actually tastes sweet.

e levan comidos moitos doces, coma nós,

e ademais aprenderon a asociar a dozura e a vainilla.

It's because even these professionals are human,

Así que o gusto, o olfacto e outra información sensorial

and have eaten lot of desserts, like us,

están indisolublemente enredadas na nosa mente consciente.

and have therefore learned to associate sweetness and vanilla.

Así que por unha banda, podemos usar isto.

So taste and smell and other sensory information

Podemos usar estas experiencias conscientes,

is inextricably entangled in our conscious mind.

usar estes datos, aproveitalos engadindo vainilla no canto de azucre

So on one hand, we can actually use this.

para edulcorar os nosos produtos.

We can use these conscious experiences,

Pero por outra banda,

use this data, exploit it by adding vanilla instead of sugar

con estas avaliacións conscientes,

aínda non sabería

se á xente realmente lle gusta o batido baixo en azucre.

to sweeten our products.

But on the other hand,

Como podemos estudar este problema?

with these conscious evaluations,

Como avaliamos o que é realidade

I still wouldn't know

tras estas conscientes avaliacións de comida?

whether people actually liked that sugar-reduced milkshake.

A clave é eliminar a barreira da consciencia

So how do we get around this problem?

How do we actually assess what's reality

e no seu lugar dirixir a información directamente ó cerebro.

behind these conscious food evaluations?

The key is to remove the barrier of the conscious mind

E resulta que

o noso cerebro garda moitos segredos fascinantes.

and instead target the information in the brain directly.

O noso cerebro recibe constantemente información sensorial de todo o corpo,

And it turns out

our brain holds a lot of fascinating secrets.

de moita da cal nin sequera somos conscientes,

como a información do gusto que recibo constantemente

Our brain constantly receives sensory information from our entire body,

do meu tracto intestinal.

most of which we don't even become aware of,

E o meu cerebro tamén actuará sobre toda esta información sensorial.

like the taste information that I constantly receive

Isto alterará o meu comportamento sen o meu coñecemento,

from my gastrointestinal tract.

And my brain will also act on all this sensory information.

e pode incrementar o diámetro das miñas pupilas

se sinto algo que me gusta.

It will alter my behavior without my knowledge,

E pode aumentar moi lixeiramente a miña produción de suor

and it can increase the diameter of my pupils

se esta emoción foi intensa.

E cun escáner cerebral,

if I experience something I really like.

agora podemos avaliar esta información no cerebro.

And increase my sweat production ever so slightly

if that emotion was intense.

En concreto, teño usado unha técnica de escáner cerebral

And with brain scans,

chamada electroencefalografía,

we can now assess this information in the brain.

abreviado EEG,

que implica levar unha gorra repleta de eléctrodos,

Specifically, I have used a brain-scanning technique

called electroencephalography,

128 no meu caso.

or "EEG" in short,

Cada eléctrodo mide a actividade eléctrica do cerebro

which involves wearing a cap studded with electrodes,

cunha precisión de ata milisegundos.

128 in my case.

Each electrode then measures the electrical activity of the brain

O problema é, non obstante,

que non só o cerebro é electricamente activo,

with precision down to the millisecond.

tamén o son o resto do corpo e o ambiente

que contén moita actividade eléctrica en todo momento.

The problem is, however,

it's not just the brain that's electrically active,

Para facer a miña investigación,

preciso minimizar todo este murmurio.

it's also the rest of the body as well as the environment

Así que lles pido ós meus participantes que fagan unha serie de cousas.

that contains a lot of electrical activity all the time.

To do my research,

Primeiro,

I therefore need to minimize all this noise.

pídolles que descansen as súas cabezas nun freo de queixelo,

So I ask my participants to do a number of things here.

para evitar demasiado movemento dos músculos.

Tamén lles pido que, mentres, miren para o centro dunha pantalla

First off,

I ask them to rest their head in a chin rest,

para evitar demasiados movementos oculares e pestanexos.

to avoid too much muscle movement.

E nin sequera pode haber deglutición,

I also ask them to, meanwhile, stare at the center of a computer monitor

así que lles pido que boten a lingua fóra da boca,

to avoid too much eye movements and eye blinks.

sobre unha cunca de vidro,

And I can't even have swallowing,

e despois deixo continuamente estímulos gustativos sobre a lingua,

so I ask my participants to stick the tongue out of their mouth

que despois escorren na cunca.

over a glass bowl,

(Risas)

E despois, simplemente para completar esta marabillosa imaxe,

and then I constantly let taste stimuli onto the tongue,

tamén lles proporciono ós meus participantes un babeiro,

which then drip off into this bowl.

(Laughter)

dispoñible tanto en rosa como en azul, segundo prefiran.

And then, just to complete this wonderful picture,

(Risas)

I also provide my participants with a bib,

Parece unha experiencia gastronómica normal, non si?

available in either pink or blue, as they please.

(Risas)

(Laughter)

Non, obviamente non.

E aínda peor,

Looks like a normal eating experience, right?

tampouco podo controlar o que os meus participantes están a pensar

(Laughter)

polo que preciso repetir este procedemento

No, obviously not.

moitas veces.

And worse,

Quizais a primeira vez, estean a pensar no xantar gratuíto

I can't even control what my participants are thinking about,

que lles dou por participar,

so I need to repeat this taste procedure

ou quizais a segunda vez, estean a pensar no Nadal que que se achega

multiple times.

Maybe the first time, they're thinking about the free lunch

e en que mercarlle á nai este ano, sabedes, non?

that I provide for participating,

Pero o común de cada resposta é a resposta ó gusto.

or maybe the second time, they're thinking about Christmas coming up

Polo que repito este procedemento moitas veces.

and what to get for Mom this year, you know.

Sesenta, de feito.

But common for each response is the response to the taste.

E despois fago unha media das respostas,

porque as non relacionadas co sabor estarán por riba da media.

So I repeat this taste procedure multiple times.

Usando este método,

Sixty, in fact.

outros laboratorios e nós,

And then I average the responses,

because responses unrelated to taste will average out.

temos investigado canto tempo pasa dende que a comida aterra na nosa lingua

ata que o noso cerebro determina que sabor está a experimentar.

And using this method,

we and other labs,

Resulta que isto xa ocorre nos primeiros 100 milisegundos,

have investigated how long a time it takes from "food lands on our tongue"

ao redor de medio segundo antes incluso de darnos conta diso.

until our brain has figured out which taste it's experiencing.

E a continuación, tamén investigamos

Turns out this occurs within the first already 100 milliseconds,

a diferenza de sabor entre o azucre e os edulcorantes artificiais

that's about half a second before we even become aware of it.

que para o noso esquema mental teñen un sabor moi similar.

And next up, we also investigated

De feito, saben tan parecido

the taste difference between sugar and artificial sweeteners

que a metade dos meus participantes case non podía distinguir o sabor,

that in our setup taste extremely similar.

e a outra metade simplemente non podía.

In fact, they tasted so similar

Pero sorprendentemente,

that half my participants could only barely tell the taste apart,

se miramos a todo o grupo de participantes

vimos que os seus cerebros podían diferenciar o sabor.

while the other half simply couldn't.

But amazingly,

if we looked across the entire group of participants,

Así que co EEG e outros sistemas de escáner cerebral

we saw that their brains definitely could tell the taste apart.

e con outras medidas fisiolóxicas...

suor e tamaño das pupilas,

temos novas portas cara ao noso cerebro.

So with EEG and other brain-scanning devices

Portas que nos axudarán a apartar a barreira da mente consciente

and other physiological measures --

para ver a través dos nesgos da xente

sweat and pupil size --

e posiblemente dar capturado diferenzas subconscientes no sabor.

we have new gateways to our brain.

Gateways that will help us remove the barrier of the conscious mind

E isto grazas a que agora podemos medir a primeirísima resposta da xente á comida

to see through the biases of people

antes de seren conscientes dela,

and possibly even capture subconscious taste differences.

e antes de que comecen a racionalizar se lles gusta ou non.

And that's because we can now measure people's very first response to food

Podemos medir as expresións faciais da xente,

podemos medir onde están a mirar,

before they've become conscious of it,

and before they've started rationalizing why they like it or not.

a súa resposta de suor,

a súa resposta cerebral.

We can measure people's facial expressions,

E con todas estas medidas,

we can measure where they're looking,

imos ser capaces de crear comidas máis saborosas,

we can measure their sweat response,

porque podemos medir se á xente realmente lle gusta

we can measure their brain response.

aquel batido baixo en azucre.

And with all these measures,

E podemos crear comidas máis saudables sen comprometer o sabor,

we are going to be able to create tastier foods,

because we can measure whether people actually like

porque podemos medir a resposta a distintos edulcorantes

that sugar-reduced milkshake.

e atopar o que nos dá unha resposta máis semellante

And we can create healthier foods without compromising taste,

á que provoca o azucre.

E amais, podemos axudar a crear comidas máis saudables,

because we can measure the response to different sweeteners

porque podemos axudar a entender como sentimos a comida

and find the sweetener that gives the response that's more similar

en primeira instancia.

to the response from sugar.

Algo sobre o que sorprendentemente sabemos moi pouco.

And furthermore, we can just help create healthier foods,

because we can help understand how we actually sense food

Por exemplo, sabemos que hai cinco sabores básicos,

in the first place.

pero sospeitamos que hai máis,

Which we know surprisingly little about.

e de feito, usando o noso EEG, atopamos evidencias de que a graxa,

For example, we know that there are those five basic tastes,

ademais de que sentimos a súa textura e olor,

but we strongly suspect that there are more,

tamén a degustamos.

and in fact, using our EEG setup, we found evidence that fat,

O que significa que a graxa podería ser ese novo sexto gusto básico.

besides being sensed by its texture and smell,

E se desciframos como o noso cerebro recoñece a graxa e o azucre,

is also tasted.

Meaning that fat could be this new sixth basic taste.

e aquí estou simplemente a soñar,

poderíamos entón algún día

crear un batido con cero calorías que saiba como o orixinal?

And if we figure out how our brain recognizes fat and sugar,

and I'm just dreaming here,

Ou quizais descubrimos que non podemos,

but could we then one day

create a milkshake with zero calories that tastes just like the real deal?

porque subconscientemente detectamos calorías

a través dos nosos receptores do tracto gastrointestinal.

Or maybe we figure out that we can't,

O futuro dirá.

because we subconsciously detect calories

A nosa experiencia consciente coa comida

via our receptors in our gastrointestinal tract.

é simplemente a punta do iceberg da nosa sensación total con ela.

The future will show.

Our conscious experience of food

E estudando esa sensación total,

consciente e subconsciente por igual,

is just the tip of the iceberg of our total sensation of food.

coido que podemos facer alimentos máis saborosos e saudables para todos.

And by studying this total sensation,

Grazas.

conscious and subconscious alike,

(Aplausos)

I truly believe that we can make tastier and healthier foods for all.

Thank you.

(Applause)