Growing up bilingual. Speaking two languages can have important benefits for the brain. That's according to Pulitzer prize winning author and professor of geography Jared Diamond.
Speaking two or more languages is common around the world but fairly rare in the US or in much of the UK. So I went to see professor Diamond from the University of California in Los Angeles to find out how new research shows how multilingualism can help us pay better attention, make better decisions and even help protect us from the ravages of Alzheimer's disease.
But first I wanted to know why as a geography professor he was so interested in languages.
Oh, I've been interested in languages for a long time. My mother was a great linguist who brought us to Europe in 1950. Mom, although she had learned German 36 years ago and never spoke German in a German city, immediately started to speak German and that impressed me. So I'm now learning my 12th language and that will be my last language. I just love languages.
12 languages! I find very impressive. I mean, multilingualism in certain Western cultures is not common, particularly of those of us who speak English. How common is it in the rest of the world?
Well, in New Guinea it is utterly routine. I've never met a New Guinean who spoke fewer than 5 languages. And there was one evening when I was in a camp with couple dozen of New Guineans and so we went around asking “what do you speak? what do you speak? what do you speak?” The New Guinean that spoke fewest languages spoke 5 languages and the champion spoke 15 languages. Also in Switzerland. I mean every educated Swiss person, every Dutch person who graduates high-school has to speak 5 languages, or, if they are Frisian, they have got to know 6 languages. So the monolingualism of Americans is embarrassingly unusual.
And you have been looking into effects that multilingualism, this ability to speak more than one language, has actually having on brains. On brain development.
I would say it's not on brain development, but on use of the brain. And I should also make clear that this fascinating work, this great work is not my own work that I am praising, but instead the work by two groups of people. One is Ellen Bialystok, professor of psychology in York University in Toronto and the other is Agnes Kovacs and Jacque Mehler at the school of advanced studies in Trieste. So it's beautiful work on life-long effects of being able to speak more than one language.
And because of your interests in languages obviously you've been looking into that research. What sort of things have you been finding?
Well. Let's start with children. There are children called crib bilingual, of whom mother speaks one language and father speaks another language. So the day the kid is coming home from the hospital he is already exposed to two different languages. And by the few months, while the kid cannot speak they are nevertheless able to distinguish sounds of these languages. It turns out that these kids, before they can speak, nevertheless have an advantage at distinguishing sounds, which you would not be surprised at, but they are just also better playing games which involve changes of rules or confusing directions. So if you flash a puppet on the screen and then you say lo-lo-vu and the baby learns to look at the left side of the screen for the puppet, and you say then vo-vo-lu and the puppet will turn to the right side of the screen, a bilingual kid will correct for this lu shift, but the monolingual kid continues to look at the wrong side of the screen at lo-lo-vu. So that's just an example that learning more than one language makes you flexible at dealing with changes of the rules, but life is full of changes of rules.
And that's just random pattern of sounds that these babies are exposed to sort of stimulating them to look in one direction or the other.
That's right. The kids were conditioned.
And what's the current thinking about whether that is going to be beneficial long-term to a child that is growing up, because the concern that some parents had, certainly historically, is that we might confuse a child trying to teach two languages. Learning one is difficult enough sometimes.
That's right. The usual belief, at least in the United States, is that learning 2 languages is bad. For example my wife is from a Polish family and my wife's parents were very careful never to speak Polish to my wife. And similarly my father came from Eastern Europe and his parents never spoke the language other than English. So the usual belief in the United States is that it's not good, it's bad to learn two languages. The actual results is that the child that's learned two languages by the age of 4 or 5 will end up with a vocabulary of 3000 words in English and 3000 words in Chinese if it's an English-Chinese bilingual. Whilst the monolingual English kid has a vocabulary of 3300 words in English. So you ask yourself: Would you rather know 3300 words of English or 3000 words of English and 3000 words of Chinese? And I would say that's no-brainer.
And that research, coupled with the research you've just mentioned about babies and their attention, does that show that there is something different in the brain as these children are developing? What's actually going on?
It suggests that yes, there is something different in the brain. What's different in the brain is that if you just stop to think what is going on at any moment when you are doing anything in life, like now, you and I are paying attention to talking to one another and I am not birdwatching which I often do and I'm not smelling my wife's gorgeous cooking. We always have to concentrate on one thing and exclude everything else. But a baby that's been reared bilingually has learned from the age of 3 months to pay attention to the sounds of Italian and to ignore the sound of mummy who speaks Chinese. But if mummy starts speaking, the baby will start paying attention to Chinese and ignore Italian. So the infant that is reared bilingually has to develop and practice paying attention that the rest of us do not develop
What about as the people get older? Do we still see the benefits in the brain of older people who have been brought up with more than one language?
It turns out that old people coming down with Alzheimer's symptoms come down with them on average 5 years later in life if they are bilingual or multilingual than if they are monolingual. In fact being bilingual protects you for about 5 years against the symptoms of Alzheimer’s disease, but Alzheimer’s disease is something that terrifies all of us. It would be really powerful if it turns out as appears to be the case that you get 5 years of protection against Alzheimer's by knowing another language. But suppose you are Swedish shopkeeper who speaks 5 languages, then you get 25 year of protection against Alzheimer's, and so you will not get it until you are a 103 years old and so you are not going to get it.
Presumably those as yet are unanswered questions.
Exactly. Those are unanswered questions. And I'm sure there are going to be a lot of arguments about it because there are lots of people who don't just like the idea of bilingualism not just being bad but being positively good.
Professor Jared Diamond there. With a good example of well how clever our brains are.
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