Babies brought up in bilingual homes learn languages by devoting their attention to the general associations between words and objects for a longer period, whereas infants raised by monolingual families learn new words by focusing on detailed sound information, researchers have found.
The discovery of different mechanics employed by monolingual and bilingual babies in learning languages is a result of a research conducted by researchers at the University of British Columbia and Ottawa.
Published in the journal Child Development, the new findings attain significance as almost all experimental works in infant language development so far have focused on children who are monolingual, a cause of scant availability of details about the learning processes involved in acquiring two languages from birth.
The researchers conducted two experiments with 14, 17 and 20 month old infants who were being raised in homes where two different languages were spoken. The first experiment involved a heterogeneous sample of babies who were exposed to English and another language, while the second experiment involved two homogeneous groups of bilingual infants exposed either to English and French or to English and Chinese.
In both experiments, infants were repeatedly presented with a crown-shaped object that was called "bih", and a molecule-shaped object called "dih". It was then tested whether the children were able to notice any change when the names of the crown-shaped and molecule-shaped objects were swapped.
The researchers found that bilingual infants in all of the study groups failed to notice the minimal change in the object's name until 20 months of age, whereas monolingual infants detected it at 17 months.
Based on their findings, the researchers reckon that ignoring the consonant detail in a new world may be an adaptive tool used by bilingual infants in learning new words.
According to them, the results of the experiments indicate that bilingual infants might be devoting more cognitive resources to making the links between words and objects, instead of paying attention to the detailed information in the word.
The researchers say that extending this approach to word learning for a few months longer than monolinguals may help bilinguals "keep up" with their peers.
Several previous studies have indeed shown that bilinguals and monolinguals achieve language-learning milestones, such as speaking their first word, at similar ages, and have vocabularies of similar sizes when words from both languages are taken into account.
"Through studies with bilingual infants, we can gain a deeper understanding of language development in all infants," said Christopher T. Fennell, assistant professor of psychology at the University of Ottawa and the lead author of the study.
"In addition, the findings emerging from such studies will have practical implications for parents who are raising their children in a bilingual environment by revealing how young bilinguals acquire language," he added.