Unraveling how children become bilingual so easily

By LAURAN NEERGAARD, AP Medical Writer Lauran Neergaard, Ap Medical Writer

Tue Jul 21, 3:08 am ET

WASHINGTON The best time to learn a foreign language: Between birth and age

7. Missed that window?

New research is showing just how children's brains can become bilingual so

easily, findings that scientists hope eventually could help the rest of us

learn a new language a bit easier.

"We think the magic that kids apply to this learning situation, some of the

principles, can be imported into learning programs for adults," says Dr.

Patricia Kuhl of the University of Washington, who is part of an international

team now trying to turn those lessons into more teachable technology.

Each language uses a unique set of sounds. Scientists now know babies are born

with the ability to distinguish all of them, but that ability starts weakening

even before they start talking, by the first birthday.

Kuhl offers an example: Japanese doesn't distinguish between the "L" and "R"

sounds of English "rake" and "lake" would sound the same. Her team proved

that a 7-month-old in Tokyo and a 7-month-old in Seattle respond equally well

to those different sounds. But by 11 months, the Japanese infant had lost a lot

of that ability.

Time out how do you test a baby? By tracking eye gaze. Make a fun toy appear

on one side or the other whenever there's a particular sound. The baby quickly

learns to look on that side whenever he or she hears a brand-new but similar

sound. Noninvasive brain scans document how the brain is processing and

imprinting language.

Mastering your dominant language gets in the way of learning a second, less

familiar one, Kuhl's research suggests. The brain tunes out sounds that don't

fit.

"You're building a brain architecture that's a perfect fit for Japanese or

English or French," whatever is native, Kuhl explains or, if you're a lucky

baby, a brain with two sets of neural circuits dedicated to two languages.

It's remarkable that babies being raised bilingual by simply speaking to them

in two languages can learn both in the time it takes most babies to learn

one. On average, monolingual and bilingual babies start talking around age 1

and can say about 50 words by 18 months.

Italian researchers wondered why there wasn't a delay, and reported this month

in the journal Science that being bilingual seems to make the brain more

flexible.

The researchers tested 44 12-month-olds to see how they recognized

three-syllable patterns nonsense words, just to test sound learning. Sure

enough, gaze-tracking showed the bilingual babies learned two kinds of patterns

at the same time like lo-ba-lo or lo-lo-ba while the one-language babies

learned only one, concluded Agnes Melinda Kovacs of Italy's International

School for Advanced Studies.

While new language learning is easiest by age 7, the ability markedly declines

after puberty.

"We're seeing the brain as more plastic and ready to create new circuits before

than after puberty," Kuhl says. As an adult, "it's a totally different process.

You won't learn it in the same way. You won't become (as good as) a native

speaker."

Yet a soon-to-be-released survey from the Center for Applied Linguistics, a

nonprofit organization that researches language issues, shows U.S. elementary

schools cut back on foreign language instruction over the last decade. About a

quarter of public elementary schools were teaching foreign languages in 1997,

but just 15 percent last year, say preliminary results posted on the center's

Web site.

What might help people who missed their childhood window? Baby brains need

personal interaction to soak in a new language TV or CDs alone don't work. So

researchers are improving the technology that adults tend to use for language

learning, to make it more social and possibly tap brain circuitry that tots

would use.

Recall that Japanese "L" and "R" difficulty? Kuhl and scientists at Tokyo Denki

University and the University of Minnesota helped develop a computer language

program that pictures people speaking in "motherese," the slow exaggeration of

sounds that parents use with babies.

Japanese college students who'd had little exposure to spoken English underwent

12 sessions listening to exaggerated "Ls" and "Rs" while watching the

computerized instructor's face pronounce English words. Brain scans a hair

dryer-looking device called MEG, for magnetoencephalography that measure

millisecond-by-millisecond activity showed the students could better

distinguish between those alien English sounds. And they pronounced them

better, too, the team reported in the journal NeuroImage.

"It's our very first, preliminary crude attempt but the gains were phenomenal,"

says Kuhl.

But she'd rather see parents follow biology and expose youngsters early. If you

speak a second language, speak it at home. Or find a play group or caregiver

where your child can hear another language regularly.

"You'll be surprised," Kuhl says. "They do seem to pick it up like sponges."