Bilingual Babies More Perceptive To Nonnative Tongues
IRA FLATOW, host:
You're listening to SCIENCE FRIDAY. I'm Ira Flatow.
Like me, you might have a nice collection of dusty Berlitz phrasebooks hanging out in your garage, left over from your last European vacation. You might even crack one open to learn to say (unintelligible) SCIENCE FRIDAY.
Speaking more than one language has added benefits to finding your way around a foreign country or perhaps speaking Spanish to your neighbor. You hear about the possibilities all the time, like sharper brains, later onset of Alzheimer's, stuff like that.
Well, this week we'll add another piece of good news: a study that suggests bilingual infants are more attentive, more perceptive to languages, even to the ones they're not hearing at home.
A promising finding for babies, how did they find that out? And is there any hope for us older students? That's what we'll be talking about, 1-800-989-8255. Or you can tweet us, @scifri, @-S-C-I-F-R-I.
Janet Werker is a professor and Canada research chair in the Department of Psychology at the University of British Columbia in Vancouver. She joins us by phone. Welcome to SCIENCE FRIDAY, Dr. Werker.
Dr. JANET WERKER (University of British Columbia): Thank you, nice to be here.
FLATOW: You're welcome. Tell us about this study. What did you find out, and what were you looking for?
Dr. WERKER: Right. It was a fun study. As you probably know, babies are prepared at birth to learn language or languages. And in previous work, we have shown that babies can discriminate languages just by watching silent talking faces.
So they see a bilingual speaker, you turn the sound off, and they can tell when it changes from one language, English, to when the person stops speaking English and starts speaking French, even with no sound.
But we had shown in previous work that by seven or eight months of age, babies who are growing up monolingual in English can't do that anymore, whereas babies who are growing up bilingual in French and English can.
So what we asked here is: Are bilingual infants learning the characteristics of each of their native languages? I mean, clearly they are. The bilingual English-French babies could maintain this sensitivity, which might help them keep English and French apart as they're acquiring them.
But what we ask now is: Is this a specific sensitivity just to the two languages that the baby is being exposed to? Or as a function of having to pay attention to the cues that will distinguish the two languages in their world, if they're growing up bilingual, do bilingual babies learn something more general? Do they learn to pay attention to the cues in language that might allow them to keep any two languages apart?
So to address this question, my colleague in Barcelona, Nuria Sebastian Gallas(ph), and I, together with our students Wendy Wycam(ph) and Barbara Albaredo(ph), asked whether Spanish Catalan bilingual infants could also keep English and French apart, languages they'd never seen before, at eight months of age.
So again, we filmed bilingual English and French speakers, and the babies saw the speakers one at a time. They saw a videotape of, let's say Speaker A reciting a sentence in English, and then again another sentence in English, Speaker B a sentence in English, et cetera.
And the babies watched for a while, and after a while the babies get bored, and they're not very interested in watching anymore.
And so then to determine whether the babies can discriminate a change from one language to the other, we show them the same women, one at a time, reciting more new sentences, either in the language they had seen before, English, or in the language they hadn't seen before, French.
And what we found is at eight months of age, monolingual Spanish babies and monolingual Catalan babies can't tell the difference, just like the English monolingual babies. However, the bilingual Spanish-Catalan babies, so babies who are growing up with two languages, Spanish and Catalan from birth, could distinguish spoken visual English from spoken visual French, even though neither of the languages was familiar.
They showed an interest in the language change and started looking longer again.
FLATOW: So they were - they paid attention, even as the language was changed.
Dr. WERKER: That's right. And so if they can't discriminate the language change, what happens is they see these same three women reciting yet new sentences in a new language, but it's the same women. And if they haven't pulled out something about the language, they'll continue to get bored, and their looking time will continue to be lower and lower.
However, if they can tell the difference between the two languages -hey, she's doing something different than she was before - then they will be interested again, just like all of us are interested in novelty, and their looking time, their attention gets longer.
FLATOW: Now, can we generalize from here to, you know, suggest that bilinguals are more perceptive in general or better at paying attention or more alert to other things besides just the speech?
Dr. WERKER: Right. I mean I think that's one of the really interesting questions. So as a function of keeping two languages apart, are bilinguals just learning about the characteristics of languages - that in itself would be quite a substantial thing to learn - but in addition, are they learning something more general?
And in the realm of perception, in my lab, we haven't really addressed that question yet. We haven't answered that question yet. But there is work from a lot of other labs that suggests that as a function of growing up bilingual, babies are learning something more general.
FLATOW: So we should not try to teach them just one language. Having a bilingual family is an advantage.
Dr. WERKER: Well, I think that's what the work shows. And I don't think it's the case that if you are monolingual you should run out tomorrow and try to learn a new language so that you can grow - you know, so you can speak two languages to your child and give them the opportunity to grow up bilingual.
I think what the work shows is that if you - if in your home more than one languages is spoken, that that's something to be comfortable with, and it's an opportunity to provide your infant with both languages because there may be advantages that accrue.
So I could tell you a little about some of the other advantages, if you wanted to hear about them.
FLATOW: Sure, give us one. Give us one or two.
Dr. WERKER: Sure, and so a claim that's made is that people who speak two languages have to have both of them active all the time. So if they're bilingual with French and English, both French and English are active all the time, but that they have to inhibit one of those languages when they're speaking the other one, and that this may confer some more general advantages in cognitive processes.
And so, for example, even in infancy, there's work that shows, this is by Agie Covax(ph) and Jacques Maylor(ph), that even at seven months of age, a baby who's growing up bilingual is - all babies are able to learn, like if they hear a particular sound, to turn their head to the right. That's easy enough, and that they'll be rewarded with something.
But a bilingual baby at seven months can learn now to inhibit that response and instead turn their head to the best(ph). That's something that's more difficult for a monolingual baby to learn.
Dr. WERKER: And people think that might have to do with their continual experience with having to shift from one language to another in acquisition.
FLATOW: So they can locate the source rather than just turning their head in one direction.
Dr. WERKER: Well, it's not so much that they're locating the source. It's that they're learning one rule and then substituting that with a second rule. And by 12 months of age, they can learn two rules simultaneously, like keeping track of the perceptual cues of each of two different languages or the structure of each of two different languages.
FLATOW: Wow, that's fascinating.
Dr. WERKER: Yeah.
FLATOW: Thank you for sharing that with us.
Dr. WERKER: You're very welcome.
FLATOW: Thanks for joining us.
Dr. WERKER: You're very welcome.
FLATOW: Good luck with your work.
Dr. WERKER: Thank you, Ira.
FLATOW: Janet Werker is a professor and Canada Research Chair in the Department of Psychology at the University of British Columbia in Vancouver.
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