Children exposed to several languages are better at seeing through others’ eyes

From the print edition of The Economist Newspaper

HUMAN beings are not born with the knowledge that others possess minds with different contents. Children develop such a “theory of mind” gradually, and even adults have it only imperfectly. But a study by Samantha Fan and Zoe Liberman at the University of Chicago, published in Psychological Science, finds that bilingual children, and also those simply exposed to another language on a regular basis, have an edge at the business of getting inside others’ minds.

In a simple experiment, Dr Fan and Dr Liberman sat monolingual, bilingual and “exposure” children aged between four and six with a grid of objects placed between them and an experimenter. Some objects were blocked from the experimenter’s sight, a fact the children could clearly see. With a large, a medium and a small car visible to the child, but the small car hidden from the adult, the adult would ask “I see a small car” and ask the child to move it. Both bilingual and those in the exposure group moved the medium-sized car (the smallest the experimenter could see) about 75% of the time, against 50% for the monolinguals. The successful children were less likely even to glance at the car the experimenter could not see.

This study joins a heap of others suggesting that there are cognitive advantages to being bilingual. Researchers have found that bilinguals have better executive function (control over attention and the planning of complex tasks). Those that suffer dementia begin to do so, on average, almost five years later than monolinguals. Full bilinguals had previously been shown to have better theory-of-mind skills.

But this experiment is the first to demonstrate that such benefits also accrue to those merely exposed to other languages.

It has become fashionable to consider as a kind of elite mental training. The question is not settled, though, for many studies have not been successfully replicated. Nor is it yet clear precisely which kinds of language skills and exposure make people better at exactly which tasks. For example, in Dr Fan’s and Dr Liberman’s experiment the bilingual children had better executive function than the exposure ones, while all three groups had similar vocabularies, fluid intelligence (the ability to reason quickly and think abstractly) and non-verbal visual-spatial skills. This makes it surprising that the exposure group resembled the bilinguals more than the monolinguals when it came to taking the experimenter’s point of view.

If the bilingual advantage is to hold up, more clever research design is needed. Some advantages may accrue only to bilinguals who switch languages often. Some may apply only to those who live in mixed communities. While some advantages, such as lack of dementia, appear late in life, others may appear early only to disappear thereafter. Research on multilingual minds is, itself, still in a kind of adolescence, but it is a promising one.

From the print edition of The Economist Newspaper