July 9 (HealthDay News) - European researchers are contesting the assumption that bilingual toddlers have more trouble learning language skills than children who know just one language.

"While the remarkable performance of children acquiring one language is impressive, many children acquire more than one language simultaneously," said study author Agnes Melinda Kovacs, a research fellow at the International School for Advanced Studies, in Trieste, Italy. "As bilingual children presumably have to learn roughly twice as much as their monolingual peers [because they learn two languages instead of one], one would expect their language acquisition to be somewhat delayed. However, bilinguals pass the language development milestones at the same ages as their monolingual peers."

The finding, which appears online July 9 in Science, came from a test of the responses to verbal and visual cues from 64 babies who were 12 months old. They came from monolingual and bilingual families, although the study did not specify which languages the families spoke.

The toddlers were exposed to two sets of words that had different structural characteristics. After each word, the children viewed a special toy on either the left or right side of a screen, depending on the word's structure. They then were presented with words they had never heard before but that conformed to one of the two verbal structures. No toy followed.

Researchers determined whether the infants had learned the word structures by measuring the direction of their gaze after hearing each new word. Judging by their eye movements, the bilingual kids did better in recognizing words than their monolingual peers.

"We showed that pre-verbal, 12-month-old, bilingual infants have become more flexible at learning speech structures than monolinguals," Kovacs said. "When given the opportunity to simultaneously learn two different regularities, bilingual infants learned both, while monolinguals learned only one of them."

This means, she said, that "bilinguals may acquire two languages in the time in which monolinguals acquire one because they quickly become more flexible learners."

According to the study, the cognitive pathways developed during the learning of two languages might make bilingual children more efficient in acquiring new information.

Earlier research has often confirmed the benefits of learning more than one language. In a 2004 Canadian study, for example, researchers found that bilingual speakers were more proficient at dealing with distractions than those who spoke only a single language. That ability was even more pronounced for older people, suggesting that multilingualism might help elderly speakers avoid age-related cognitive problems.

A significant percentage of humanity speaks more than one language. In the United States, more than 18 percent of the population aged 5 and older speaks a language other than English at home, according to the 2000 U.S. census.

One child psychologist who read the Italian study found the results intriguing and said she would like to see further research on how children learn different languages, especially ones with different tonal structures, such as Chinese and English.

"We now know, thanks to [functional MRI] studies that allow us to observe the working brain, that learning does result in discrete changes in 'wiring,'" said Marta Flaum, whose practice in Chappaqua, N.Y. specializes in diagnosing and helping children with dyslexia and other language handicaps. "It would make sense that learning a second language affects brain changes as well."

However, Flaum said, "we know that the young brain is more plastic than the older brain, making it easier to learn at an earlier age."

SOURCES: Agnes Kovacs, Ph.D., research fellow, International School for Advanced Studies, Trieste, Italy; Marta Flaum, Ph.D., child psychologist, Chappaqua, N.Y.; July 9, 2009, Science, online