The
Prospero blog on
Economist.com today
examines bilingual education, and the data it presents is dramatic:
"The benefits ... are both strong and long-lasting. Bilingual children as young as seven months outperform monolinguals at tasks requiring “executive function”: prioritising and planning complex tasks and switching mental gears ... [s]uch studies control for socio-economic status, and in fact the same beneficial effects have been shown in bilingual children of poor families. Finally, the effects appear to be lifelong: bilinguals have later onset of Alzheimer’s disease, on average, than do monolinguals ..."
"Many parents once believed that a second language was a bad idea, as it would interfere with developing the first and more important one. But such beliefs are woefully out of date today. Some studies (such as this one) seem to show that bilinguals have smaller vocabularies in each language (at early stages) than monolinguals do. But other studies (such as this one) find no vocabulary shortfall in either language. In any case, the influence of mono- or bilingualism on vocabulary size is later overtaken by the importance of education, socio-economic status, reading and writing habits. In short, there is little evidence that raising a child bilingual will hurt their primary language."
The columnist speculates that the benefit of the second language comes from monitoring the use of two languages (
which is itself an exercise of the executive function), and that seems to make a certain amount of sense. Interestingly, the author also notes that the benefits of bilingualism wither unless the student
must use the language in certain circumstances -- either at home, work, or school -- which explains a lot about the power of dual immersion ...
