Science Friday on NPR reports on a new study of bilingual infants that suggests a bilingual upbringing outfits infants with more sensitive language perception abilities, even for languages other than the two spoken at home. Psychologist Janet Werker of the Infant Studies Centre, University of British Columbia discusses the findings, and whether the trend may hold true through the years.

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 … 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.

[An interesting question is whether] 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.

Yahoo! reports on a new study that shows the mental health benefits of speaking two languages.

Bialystok studied 450 Alzheimer’s patients, all of whom showed the same degree of impairment at the time of diagnosis. Half are bilingual — they’ve spoken two languages regularly for most of their lives. The rest are monolingual.

The bilingual patients had Alzheimer’s symptoms and were diagnosed between four and five years later than the patients who spoke only one language.