Núria Sebastián Gallés: "There is no solid evidence that being bilingual gives us a cognitive advantage."

BarcelonaA four-month-old baby, sitting on its mother's lap, looks at a screen displaying dinosaurs of different colors and sizes, and, from time to time, phrases in Chinese can be heard. Across the room, a team of researchers scrutinizes the baby's reactions and records reaction times to stimuli. This is one of the experiments conducted at the Childhood Research Laboratory at the Center for Brain Cognition (CBC) at Pompeu Fabra University (UPF), where they attempt to decipher questions such as how we perceive language before speaking or how we face the challenge of learning two languages ​​instead of one.

It is in this area of ​​cognitive neuroscience and bilingualism that neuroscientist Núria Sebastián Gallés (Barcelona, ​​​​1958), professor of psychology at this university and leader of the language acquisition and processing (SAP) group, speaks. For this reason, this Friday he received the 2024 National Research Award, the highest scientific award in Catalonia, granted by the Catalan Foundation for Research and Innovation and the Government, and which recognizes researchers who have significantly contributed to science on an international scale.

The awards also recognized ex aequo In the Young Talent category, Icrea researchers Eva Maria Novoa, from the Center for Genomic Regulation (CRG), and Xavier Ros Oton, Professor in the Department of Mathematics and Computer Science at the University of Barcelona (UB). In the scientific patronage category, the award went to the FERO Foundation for this 35th edition. The San Juan de Dios Hospital received an award in the Promoting Knowledge Transfer category for the i4KIDS initiative; and finally, the Fisidabo project, from the UPC and Tibidabo, was recognized in the scientific communication category.

What prompted you to study how we learn to speak?

— In my fourth year of psychology, I had a class, Experimental Psychology, where we conducted experimental research on how language is processed. I remember sitting in class and saying, "Wow! How do I say that?" table"It's incredible, but I know how to do it, and I have no idea how." Then, due to life circumstances, and in that case, a young man—we thought we were the nine Curies of psychology [laughs heartily, what do you want]—I started to look into research topics. And, of course, studying language in a place like Barcelona, ​​​​where the population is bilingual.

And how do we do it?

— I wish I could answer that question! But if we don't even know how we do it with one, imagine with two! We have notions about how we learn and produce language, but we're far from fully understanding it because that would require understanding how the human mind works. When we started our research, in the 1980s, there were no techniques to observe what happened in the brain. The existing knowledge was based on patients who had suffered injuries or post-mortem samples. Then the first tools came out to observe how the brain worked in real time, and we began to be able to investigate whether the minds of monolinguals and bilinguals were different; how they learned languages, what brain networks were involved. And we began to see that, basically, the same structures and mechanisms are involved. In other words, both languages come from the same place, which makes it even more mysterious.

But he does find some differences.

— Most of the differences we find reflect the difficulty we may have in the second language. That is, the less knowledge you have of a second language, the more differences you find at the brain level in terms of the effort required. However, the more proficient you are with two languages, the fewer differences there are.

Does exposure to two or more languages delay the onset of speech?

— In one of the first studies we published, at the University of Barcelona, ​​we showed that infants between four and six months old were able to discriminate between Catalan and Spanish, both monolingual and bilingual. Being exposed to two languages ​​didn't slow them down compared to the abilities of babies who only spoke one. I remember that a newspaper at the time that covered the study dedicated a page to the study and ran the headline: "Spanish doesn't scare Catalan babies."

This wasn't it, was it?

— Not exactly. This study, published in 1997, is considered the first experimental study of bilingual acquisition in children.

He created a new field of research.

— We didn't realize it at the time. We had just launched the infancy lab and had spent two years collecting data, because studies with infants are very, very slow. In that first study, we looked at infants' response time to orient to sentences. We sat the infants in front of a screen where something caught their attention appeared. Then, through speakers located to the right or left, we played sentences like: "She looked out the window and saw it was snowing." When the sentence began, the visual stimulus disappeared, and we calculated the time it took the infant to orient to the side from which the sound had been heard. In previous studies, we had found that they did so more quickly when the stimulus was familiar, while, conversely, they took longer when it was unfamiliar.

And what happened?

— I remember the BBC came to do a report. We had a bilingual baby in the studio who looked exactly like Winston Churchill, and it was very funny because the child showed very clearly and expressively what was happening. When he heard his mother tongue, he would stare at the black screen for a second and turn his head to one side. However, when another language he didn't know appeared, he would make a tremendously funny face, as if to say, "What's this?" and then turn toward the sound. Babies take longer to look, not because they can't detect the other language, but because they're amazed. Likewise, we've conducted further studies to try to understand why this happens and are now working with the Institute of Photonic Sciences (ICFO) to design a prototype that allows us to observe the activity of certain brain structures. We've been trying to understand this strange result since 1997.

Are there differences when learning to speak between monolinguals and bilinguals?

— Whether the baby is learning Tagalog and English in British Columbia, or French and English, or Catalan and Spanish, all studies consistently repeat the same thing: that the differences between monolinguals and bilinguals are minimal, and that the underlying mechanisms are the same. There is only one aspect in which children who learn Catalan and Spanish are found to be different from the rest.

Which?

— All babies up to four months old, on average, look at their eyes more than their mouths. Then, a period begins in which they look at their mouths more, and towards the end of the first year of life, they begin to look at their eyes more, approaching how we adults do. Right from six months on, when they are learning many of the properties of their own language, when phonemes are established, and they begin to say words, the mouth helps them, giving them more information that adds to their hearing. Just as adults do, we look more at the mouth of the person speaking to us when there is a lot of noise, or when the language is difficult to understand. Well, bilinguals have been shown to lower their gaze to their mouths sooner and remain there longer. A minuscule difference that shows that children adapt to the characteristics of their environment.  

Do girls learn to speak earlier than boys?

— I love that you ask this because it's also a lie! One of the areas where girls are shown to be more advanced than boys is in word knowledge. In these studies, parents are given lists of words and asked whether they think their sons and daughters know or say them. When they are young babies, up to 15 or 18 months, there are no differences between boys and girls. It's true that they don't know many words either, nor do they speak. From a certain age, up to three years old, girls seem to know more. But when we "ask" children directly, those of us who research language find no differences, just as scientists who study the brains of adults have not found any.

What are the reasons for these differences in vocabulary?

— Most likely, when parents are asked how many words their daughter knows, being a girl, they assume she should know more. This is a bias, the observer bias, whereby you report what you expect to happen. And this also occurs with bilinguals. If you evaluate the number of words known by monolinguals and bilinguals based on knowledge of only one of the two languages, it's clear that monolinguals will know many more words, for example, in Catalan. But if you look at the words known by bilinguals in both languages, they will probably know more.

But less of each.

— Oh no! Because if Mom is saying it all the time glasses and the creature has never heard glasses Because the Pope doesn't wear one, it's clear that he can't know what his name is. glassesLanguage is not a simple science. In fact, we recently published a rather extensive study in which we examined whether the similarity of two words in two languages facilitates learning. We found that, for words that are not very common in the vocabulary of many two-year-olds, such as rabbit/rabbit, it helps that the words are similar. But if the words are very frequent, such as cat/cat, we did not observe any benefit.

And does speaking two or more languages give us any cognitive advantage?

— You ask the person who thinks all this isn't reliable. There are as many studies showing that bilingualism confers some advantage as there are studies showing that it doesn't. When there's so much evidence for and against, it means there's no solid evidence.

Why is it important to study the language?

— Because it can shed light on the brain and, ultimately, on our humanity. We are the only species that has this complex language, which is a biological function produced by the organ called the brain.

Does language enable thought?

— Babies are both capable of speech and non-speech. They have, for example, concepts that they will later name with one of the most sophisticated elements of language: quantifiers: some, none, many...That's very abstract! Because three It can be a lot, a little, or all of it, depending on the context. And young babies already know this.