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 becomebilingual so easily, findings that scientists hope eventually couldhelp 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 foradults," says Dr. Patricia Kuhl of the University of Washington,who is part of an international team now trying to turn thoselessons into more teachable technology.
Each language uses a unique set of sounds. Scientists now knowbabies are born with the ability to distinguish all of them, butthat ability starts weakening even before they start talking, bythe first birthday.
Kuhl offers an example: Japanese doesn't distinguish between the"L" and "R" sounds of English -- "rake" and "lake" wouldsound the same. Her team proved that a 7-month-old in Tokyo and a7-month-old in Seattle respond equally well to those differentsounds. But by 11 months, the Japanese infant had lost a lot ofthat ability.
Time out -- how do you test a baby? By tracking eye gaze. Make afun toy appear on one side or the other whenever there's aparticular sound. The baby quickly learns to look on that sidewhenever he or she hears a brand-new but similar sound. Noninvasivebrain scans document how the brain is processing and imprintinglanguage.
Mastering your dominant language gets in the way of learning asecond, less familiar one, Kuhl's research suggests. The braintunes out sounds that don't fit.
"You're building a brain architecture that's a perfect fit forJapanese or English or French," whatever is native, Kuhl explains-- or, if you're a lucky baby, a brain with two sets of neuralcircuits dedicated to two languages.
It's remarkable that babies being raised bilingual -- by simplyspeaking to them in two languages -- can learn both in the time ittakes most babies to learn one. On average, monolingual andbilingual babies start talking around age 1 and can say about 50words by 18 months.
Italian researchers wondered why there wasn't a delay, andreported this month in the journal Science that being bilingualseems to make the brain more flexible.
The researchers tested 44 12-month-olds to see how theyrecognized three-syllable patterns -- nonsense words, just to testsound learning. Sure enough, gaze-tracking showed the bilingualbabies learned two kinds of patterns at the same time -- likelo-ba-lo or lo-lo-ba -- while the one-language babies learned onlyone, concluded Agnes Melinda Kovacs of Italy's International Schoolfor Advanced Studies.
While new language learning is easiest by age 7, the abilitymarkedly declines after puberty.
"We're seeing the brain as more plastic and ready to create newcircuits before than after puberty," Kuhl says. As an adult,"it's a totally different process. You won't learn it in the sameway. You won't become (as good as) a native speaker."
Yet a soon-to-be-released survey from the Center for AppliedLinguistics, a nonprofit organization that researches languageissues, shows U.S. elementary schools cut back on foreign languageinstruction over the last decade. About a quarter of publicelementary schools were teaching foreign languages in 1997, butjust 15 percent last year, say preliminary results posted on thecenter's Web site.
What might help people who missed their childhood window? Babybrains need personal interaction to soak in a new language -- TV orCDs alone don't work. So researchers are improving the technologythat adults tend to use for language learning, to make it moresocial and possibly tap brain circuitry that tots would use.
Recall that Japanese "L" and "R" difficulty? Kuhl andscientists at Tokyo Denki University and the University ofMinnesota helped develop a computer language program that picturespeople speaking in "motherese," the slow exaggeration of soundsthat parents use with babies.
Japanese college students who'd had little exposure to spokenEnglish underwent 12 sessions listening to exaggerated "Ls" and"Rs" while watching the computerized instructor's face pronounceEnglish words. Brain scans -- a hair dryer-looking device calledMEG, for magnetoencephalography -- that measuremillisecond-by-millisecond activity showed the students couldbetter distinguish between those alien English sounds. And theypronounced them better, too, the team reported in the journalNeuroImage.
"It's our very first, preliminary crude attempt but the gainswere phenomenal," says Kuhl.
But she'd rather see parents follow biology and exposeyoungsters early. If you speak a second language, speak it at home.Or find a play group or caregiver where your child can hear anotherlanguage regularly.
"You'll be surprised," Kuhl says. "They do seem to pick it uplike sponges."