Toddlers that are learning two languages are also learning another skill: how to look at problems in creative new ways. If they have experience switching between languages, then they’ll be even better. The key, says a new study , is this switching.

Both bilingual and monolingual kids were studied at 24 months, and then again, seven months later, to asses their vocabularies. On the second occasion, the toddlers were also tested for a variety of factors. In general, there were few differences between the bilingual and monolingual kids, but in one area—conflict inhibition—the bilingual kids performed a lot better.

Conflict inhibition is, in this case, the ability to disregard the rules you have learned. This is obvious in the context of language—you need to be able to forget a grammar rule in one language to construct a sentence in another. But the researchers, led by Cristina Crivello of Concordia University, Montréal, found that the conflict inhibition also applied to non-language tasks.

Here are the tests that were administered:

Reverse categorization—participants were told to put a set of little blocks into a little bucket and big blocks into a big bucket. Then the instructions were switched—big blocks in the little bucket and little blocks in the big bucket. Shape conflict—participants were shown pictures of different sized fruit and asked to name them. Then a new series of images was shown, with a small fruit embedded inside a large one. Toddlers were asked to point to the little fruit.

The bilingual children did much better than kids who spoke just one language. “In conflict inhibition, the child has to ignore certain information—the size of a block relative to a bucket, or the fact that one fruit is inside another,” says Crivello. “That mirrors the experience of having to switch between languages, using a second language even though the word from a first language might be more easily accessible.”

Further, the more switching kids did, the better they performed. This was measured by recording how many language pairs they knew—the words for the same object in different languages, for example.

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The advantages of bringing up children with more than one language are already obvious. But what may be surprising is that more than half the world’s population is at least bilingual, using more than one language regularly. According to François Grosjean, writing in Psychology Today, 35% of Canada is bilingual, and 20% of the U.S. In general, as countries get smaller, the number of languages goes up. And of course, non-English natives have an advantage here, as they’re more likely to learn English as a second, international language.