Bilingual babies
May be smarter than unilingual ones, and they may do better in old age, too, scientists say.
They may mix words in one sentence in a charming mélange of franglais or Spanglish but dual-language babies may be smarter than those who babble in only one lingo.
Scientists are finding there are “cognitive advantages” to bringing up baby in a bilingual home. Plus, bilingualism seems to confer benefits at both ends of the age spectrum by protecting seniors against dementia.
But initially, a setback. Vocabularies of babies under age 2 are slightly smaller when parents mix elements from two different languages in the same sentence, a new study from Concordia University found.
But growing up bilingual does not confuse a baby and make learning to speak more difficult, rather it gives them an edge, a growing body of research suggests. They may be slower in picking up each language than children raised speaking just one, but that temporary drawback is offset by the benefits of bilingualism, said Concordia University psychology professor Krista Byers-Heinlein.
According to one estimate, 66 per cent of the world’s children are bilingual. With the rise of global bilingualism, researchers wondered: What is the linguistic environment of such babies?
Done in collaboration with psychologist Janet Werker of the Infant Studies Centre in Vancouver, B.C., the study recruited 181 parents who are themselves speakers of English and at least one other language.
Turns out most of the babies were learning two languages simultaneously. Up to 90 per cent of parents switched with ease from one tongue to another in the same breath when interacting with their children, the study found.
“It’s a normal part of being a parent of a bilingual child,” said Byers-Heinlein, director of the Concordia Infant Research Laboratory and member of the Centre for Research in Human Development. A few parents adopted a method of “one-parent, one language” but in reality, most mixed their languages regularly. Either they couldn’t find an adequate translation for particular words in a current language or they used the mix as a teaching strategy for new words, ByersHeinlein said.
The greater the language mix, the greater the challenge for the babies and the smaller their vocabularies, Byers-Heinlein said, perhaps because it’s harder to pick up meaning from a mixed-word phrase. “But this is also a strength because we know from other studies that bilinguals can tell two languages apart from birth,” she said.
Fetal hearing is fully developed by the third trimester of pregnancy and the babies “are listening” in on their mothers 24/7, she said.
In a previous study, ByersHeinlein’s lab compared 2-day-old infants of mothers who spoke two languages during their pregnancies with babies of single-language moms. There was a marked difference at birth. Babies of bilingual moms recognized both their languages.
Byers-Heinlein distinguished between the two groups by measuring how often newborns sucked on pacifiers (that were hooked to a computer) in response to sounds. Monolingual babies preferred their own language over a stranger’s, while in bilingual babies, both their familiar language sounds elicited active suckling, the study found.
A decade of studies in Canada suggests bilingual children perform better on cognitive tests than monolingual kids who only speak English. Researchers believe that the effort of juggling or switching between languages is what gives the brain massive practice and a cognitive edge thanks to improved neural circuits in the frontal region of the brain needed to execute such control.
Individuals who are fully bilingual constantly have both languages activated at all times, even during monolingual situations where they are using one language, explained Toronto psychologist Ellen Bialystok of York University, whose team last year showed bilingualism may delay the onset of Alzheimer’s disease.
But it’s not yet clear if bilingualism provides increased resistance to Alzheimer’s.
“Our view at the moment is that the enhanced executive control network that bilinguals have developed compensates for failing memory networks (which are in the middle of the brain),” Bialystok told The Gazette. “This allows them to function at a higher level than they would normally with the disease.”
John Breitner, director of the Centre for Studies on the Prevention of Alzheimer’s disease at Montreal’s Douglas Mental Health University Institute, agreed. For one thing, it’s not clear what came first, bilingualism or a robust brain that seeks stimulation, Breitner said. “Maybe bilingualism is protective, or maybe those are the kind of households where, when people grow up, they have less dementia.”
The best evidence comes from randomized trials on brain stimulation that aim to tease apart pre-disposition from protective effects. Brain stimulation definitely has benefits, Breitner said. “Whether that lasts is another question and whether that means they are protected against Alzheimer’s is another.”