The New York Times, October 11, 2011, by Perri Klass MD — Once, experts feared that young children exposed to more than one language would suffer “language confusion,” which might delay their speech development. Today, parents often are urged to capitalize on that early knack for acquiring language. Upscale schools market themselves with promises of deep immersion in Spanish — or Mandarin — for everyone, starting in kindergarten or even before.
Yet while many parents recognize the utility of a second language, families bringing up children in non-English-speaking households, or trying to juggle two languages at home, are often desperate for information. And while the study of bilingual development has refuted those early fears about confusion and delay, there aren’t many research-based guidelines about the very early years and the best strategies for producing a happily bilingual child.
But there is more and more research to draw on, reaching back to infancy and even to the womb. As the relatively new science of bilingualism pushes back to the origins of speech and language, scientists are teasing out the earliest differences between brains exposed to one language and brains exposed to two.
Researchers have found ways to analyze infant behavior — where babies turn their gazes, how long they pay attention — to help figure out infant perceptions of sounds and words and languages, of what is familiar and what is unfamiliar to them. Now, analyzing the neurologic activity of babies’ brains as they hear language, and then comparing those early responses with the words that those children learn as they get older, is helping explain not just how the early brain listens to language, but how listening shapes the early brain.
Recently, researchers at the University of Washington used measures of electrical brain responses to compare so-called monolingual infants, from homes in which one language was spoken, to bilingual infants exposed to two languages. Of course, since the subjects of the study, adorable in their infant-size EEG caps, ranged from 6 months to 12 months of age, they weren’t producing many words in any language.
Still, the researchers found that at 6 months, the monolingual infants could discriminate between phonetic sounds, whether they were uttered in the language they were used to hearing or in another language not spoken in their homes. By 10 to 12 months, however, monolingual babies were no longer detecting sounds in the second language, only in the language they usually heard.
The researchers suggested that this represents a process of “neural commitment,” in which the infant brain wires itself to understand one language and its sounds.
In contrast, the bilingual infants followed a different developmental trajectory. At 6 to 9 months, they did not detect differences in phonetic sounds in either language, but when they were older — 10 to 12 months — they were able to discriminate sounds in both.
“What the study demonstrates is that the variability in bilingual babies’ experience keeps them open,” said Dr. Patricia Kuhl, co-director of the Institute for Learning and Brain Sciences at the University of Washington and one of the authors of the study. “They do not show the perceptual narrowing as soon as monolingual babies do. It’s another piece of evidence that what you experience shapes the brain.”
The learning of language — and the effects on the brain of the language we hear — may begin even earlier than 6 months of age.
Janet Werker, a professor of psychology at the University of British Columbia, studies how babies perceive language and how that shapes their learning. Even in the womb, she said, babies are exposed to the rhythms and sounds of language, and newborns have been shown to prefer languages rhythmically similar to the one they’ve heard during fetal development.
In one recent study, Dr. Werker and her collaborators showed that babies born to bilingual mothers not only prefer both of those languages over others — but are also able to register that the two languages are different.
In addition to this ability to use rhythmic sound to discriminate between languages, Dr. Werker has studied other strategies that infants use as they grow, showing how their brains use different kinds of perception to learn languages, and also to keep them separate.
In a study of older infants shown silent videotapes of adults speaking, 4-month-olds could distinguish different languages visually by watching mouth and facial motions and responded with interest when the language changed. By 8 months, though, the monolingual infants were no longer responding to the difference in languages in these silent movies, while the bilingual infants continued to be engaged.
“For a baby who’s growing up bilingual, it’s like, ‘Hey, this is important information,’ ” Dr. Werker said.
Over the past decade, Ellen Bialystok, a distinguished research professor of psychology at York University in Toronto, has shown that bilingual children develop crucial skills in addition to their double vocabularies, learning different ways to solve logic problems or to handle multitasking, skills that are often considered part of the brain’s so-called executive function.
These higher-level cognitive abilities are localized to the frontal and prefrontal cortex in the brain. “Overwhelmingly, children who are bilingual from early on have precocious development of executive function,” Dr. Bialystok said.
Dr. Kuhl calls bilingual babies “more cognitively flexible” than monolingual infants. Her research group is examining infant brains with an even newer imaging device, magnetoencephalography, or MEG, which combines an M.R.I. scan with a recording of magnetic field changes as the brain transmits information.
Dr. Kuhl describes the device as looking like a “hair dryer from Mars,” and she hopes that it will help explore the question of why babies learn language from people, but not from screens.
Previous research by her group showed that exposing English-language infants in Seattle to someone speaking to them in Mandarin helped those babies preserve the ability to discriminate Chinese language sounds, but when the same “dose” of Mandarin was delivered by a television program or an audiotape, the babies learned nothing.
“This special mapping that babies seem to do with language happens in a social setting,” Dr. Kuhl said. “They need to be face to face, interacting with other people. The brain is turned on in a unique way.”
All Children Have a Natural Curiosity, So Why Not Nurture It with Ongoing Science Education, Which Starts at Home, then School
Students from Mark Twain I.S. 239 studied salamanders on Staten Island this week.
In September, the students trekked to the Hudson Highlands to collect data on the specimens there.
New York Students checking out Long Island Sound
The New York Times, October 11, 2011, by Lisa W. Foderaro — “Be careful!” shouted a seventh grader from Coney Island’s Mark Twain Intermediate School 239 for the Gifted and Talented.
“Don’t grab him by the tail,” warned another.
“I think he’s scared,” said a third.
The students were gathered around a red-backed salamander deep in the woods on Staten Island. A shiny black squiggle, it was jumping around in the cupped hands of their teacher, Aimee Kemp, who was determined to show them how she could tell it was a male.
New York City used to be salamander central, but while the red-backed salamander still thrives under rocks and logs, other species have disappeared.
The tiger salamander was gone by the 1930s, the marbled salamander by the 1970s. The four-toed salamander was last spotted in 1979. These days, the northern dusky salamander is found in only one location in Manhattan, Highbridge Park in Upper Manhattan, while the spotted and northern red salamanders are considered rare.
Concern about their decline in the area is not merely academic. Salamanders help protect woodlands by eating the bugs and grubs that consume leaf litter, which provides a habitat as well as crucial nutrients and moisture for wildlife and young plants. Highly sensitive to changes in the environment, salamanders are also important indicators of overall forest condition.
So in an ambitious citizen-science project, the city’s Department of Parks and Recreation has enlisted scores of seventh graders from public and private schools to study salamanders in the wild — or what passes for the wild in New York.
On a crisp fall day, five large groups of students fanned out to parks in four boroughs, with the group led by Ms. Kemp heading to High Rock Park in Staten Island’s Greenbelt. They outlined 100-square-meter transects, or sections of land, and recorded each salamander: its species, size and cover object (logs, rocks or leaf litter). They also noted other amphibians, like frogs, as well as insects, spiders and earthworms.
Despite their recent vulnerability, salamanders make ideal research subjects for children, in part because they are easy to find. “People don’t take them seriously because they’re small, cute and kind of common,” said Ellen Pehek, the parks department’s principal research ecologist. “But their commonness is precisely why we study them.
“They actually have a big impact on forest ecology. They are so numerous that they can regulate the population of invertebrates they eat. They respond to a lot of things that happen in a forest, like pollutants or erosion or restoration. It doesn’t take 10 years to see a response.”
The same students also went on a field trip to Black Rock Forest in the Hudson Highlands, 50 miles north of the city, in September to document salamanders there.
In addition to the red-backed salamander, Ms. Kemp’s students uncovered the eastern newt, while other school groups found salamanders of the slimy, northern two-lined, northern red and four-toed species. The groups will now return to the classroom and enter their data on computers, giving the city’s scientists fresh comparisons between urban salamanders and their country cousins.
The data will feed into continuing research that Dr. Pehek and others have done on salamanders in newly restored woodland areas in Inwood Hill Park in Manhattan.
There, from 2001 to 2003, the parks department removed invasive plant species like vines and honeysuckle bushes. Researchers found that, at first, bigger, feistier salamanders retreated to untouched sections of forest, claiming that territory for themselves.
The smaller, more defenseless salamanders remained in the newly restored area, but over time, the larger ones returned to join them. That meant the salamanders were able to overcome the initial disruption of the restoration, which will ultimately improve their habitat.
Ms. Kemp’s 45 students, from Mark Twain I.S. 239, found only the most common salamander, the eastern red-backed, on the trip to Staten Island. Nonetheless, a squeal went up each time they located another specimen. “I like the feeling of how they move,” said Sean Seneviratne, 12. “Their bodies are really flexible, and when you feel their spine, it makes you think about what they have that you don’t and what you have that they don’t.”
Ms. Kemp, 23, graduated from Columbia University with a degree in environmental biology. For her senior research thesis, she studied the impact of invasive plant species and earthworms on salamanders at Black Rock Forest, so she knows firsthand the importance of getting budding scientists into the field.
“You can do labs all day in the classroom, but it’s not the same as getting out there and seeing how research actually happens,” she said. “It reinforces the scientific method.”
For some students, like Savanah Hernandez, the excursions provided more than a first contact with salamanders; the trip to Black Rock Forest was her inaugural visit to the woods. Sarah Aucoin, director of the parks department’s Urban Park Rangers, said she was struck by the students’ receptiveness.
“For many of the students, it was their first time looking under a rock,” she said. “I walked up on plenty of children with millipedes crawling on their arms. Young people have a natural affinity for nature, particularly for wildlife. People learn to become squeamish. But if we can get them out there early enough and turn that curiosity into scientific inquiry, then we’re getting them on the right path.”
In addition to documenting salamanders and insects, the educators asked the students to measure the depth of the leaf litter and to estimate the size of the tree canopy overhead: was more than half of the sky covered by trees and branches or less than half?
The students also learned about the different colorations of the red-backed salamander. As might be expected from the name, most have a red stripe down their backs, but some do not, and those without the stripe are better able to tolerate dry conditions and heat.
The big idea that Ms. Aucoin hoped the students would take away is the “web of life” and how even things like downed trees and leaf litter — not to mention salamanders and insects — enhance that web. That message seemed to get across to Melanie Smith, 11, an aspiring marine biologist who found a red-backed salamander (with stripe) under a log.
“Each animal has a job,” she said as she walked back through fallen leaves to a waiting bus. “It’s like a little community.”
School trip to a farm – baby goat
Checking Out a Bug
It’s On Your Shoulder
FireFlies on a Summer Night