The newest salvo in the psychology’s “reproducibility crisis” is not in social psychology, but is hitting the field of psycholinguistics. In this case, the evidence is mounting that the so called “bilingualism advantage” may not be an advantage after all. Worse, it may be something like the Mozart Effect for psycholinguistics…That is, an effect that is plausible and desirable enough (and marketable) that we all believe it and ignore reputable counter evidence.

Full disclose, our children have attended a French Immersion school, and as we live in a country with two official languages, I think it’s important to know some of both. But I’m not bilingual myself (6 years of German in high school and university, but I no longer speak it). So I like the idea of a second language. And I like the idea of the bilingual advantage too. I’ve assumed that this advantage is present and measurable, but now I’m not so sure. This controversy is worth paying attention to.

The Bilingual Advantage

The story goes like this. People who speak two languages fluently are constantly switching between them. They have to inhibit one language in order to respond in the other. And because switching and inhibition are two of most well-known and well-studied aspects of the cognitive control system known as the executive functions, it’s assumed that bilinguals would be especially adept at these behaviours. And if they are good and switching and inhibiting within language, they may have a general executive functioning advantage for behaviours as well.

Ellen Bialystok at York University and others have investigated this claim and have produced quite a lot of data in favour of the idea that general executive functioning abilities are superior in bilinguals relative to English speaking persons. The advantages might also persist into old age and the may guard against cognitive decline in aging. Dr. Bialystock’s work is extensive has relied on many different measures and she’s arguably one of the towing figures in psycholinguistics.

Does this work Generalize?

An article in Feb 2016 in The Atlantic has suggested that recent attempts to replicate and generalize some of this work have not been successful. Specifically, the work of  Kenneth Paap, at San Francisco State has argued that there is no general advantage for bilinguals and that any advantages are either very local (confined to language) or are artifacts of small sample size studies with idiosyncratic groups. Systematic attempts to replicate the work have not been successful. Reviews of published studies found evidence of publication bias. And other psychologists have found the same thing. In other words, according to Paap, whatever advantages these groups might have shown in early studies, they can’t really be attributed to bilingualism.

The Battle Lines

By all accounts, this is a showdown of epic proportions. According to the Atlantic article, Paap has thrown the gauntlet down and said  (paraphrased) “Let’s work together, register the studies, collect good data, and get to the bottom of it.” Even a co-author of one of the most well-cited bilingualism advantage papers is now questioning the work. My colleague at Western, J. Bruce Morton, is quoted as saying:

“If people were really committed to getting to the bottom of this, we’d get together, pool our resources, study it, and that would be the end of the issue. The fact that people won’t do that suggest to me that there are those who are profiting from either perpetuating the myth or the criticism.”

But proponents of the advantage are not interested in this, suggesting that the Paap and others are not properly controlling their work and also pointing to their recent work with brain imaging (which gets away from the less than idea executive functioning tasks but also could fall prey to the Seductive allure of Neuroscience…which is another topic for another day).

This is, I think, a real scientific controversy. I think we should get to the bottom of it. If the advantage is robust and general, then it’s going to show up in these newer studies. If it’s not, then it becomes an outmoded idea (like so many in psychology and in science). That’s progress. There is the risk that inherent appeal of the advantage will allow it to persist even if the science does not back it it, and that’s problematic.