Probing Question: Are there real benefits to being bilingual?

By Melissa Beattie-Moss
June 10, 2015

There's an old joke that asks, "If someone who speaks many languages is multilingual, and someone who speaks two languages is bilingual, what do you call someone who speaks one language?"

Answer: "An American."

Does the U.S. deserve its reputation for lagging behind the rest of the world in language learning? If so, what are we failing to grasp about the importance of being bilingual?

We are making progress, but still have a way to go, says Karen Miller, director of Penn State's Language Acquisition Lab and assistant professor of Spanish linguistics.

"President Obama has made statements in favor of bilingual education, primarily in response to proponents of the English-only Movement, a political movement to make English the official language," she says. "He has pointed out that immigrant children to the U.S. will eventually become bilingual, speaking both their native language and English. And he has also said that American parents in monolingual contexts should be just as ambitious in terms of finding opportunities for their children to learn a second language, as speaking more than one language can be socially and academically beneficial to all of us throughout our lives."

While 56 to 99 percent of people in European nations are functionally bilingual, only around 20 percent of Americans can make the same claim. Says Miller, if we increase our commitment to language education, more of our citizens would be able to reap the benefits it provides.

For example, our capacity for attentional or cognitive control -- the ability to focus on certain information and ignore other information -- seems to be strengthened by bilingualism.

"Bilingual speakers have two languages, both of which are always activated, regardless of whether the individual is aware of that activity or not," Miller explains. "Psycholinguistic research indicates that this continuous co-activation of two languages produces competition, so that the bilingual person is functionally a mental juggler, with the words, grammar, and sounds of both languages available, at least momentarily, when a bilingual is attempting to use one language alone. The hypothesis is that bilinguals learn to resolve cross-language competition and, in the process, acquire cognitive control that enables them to resolve competition more generally when other non-language cognitive processes conflict."

There are many valid reasons to promote bilingualism, says Miller. "The bilingual experience appears to confer a set of positive consequences to cognition that provide increased mental flexibility for bilinguals at all ages. Research suggests it may even provide protections against the symptoms of dementia for those developing pathology."

Unfortunately, some news outlets have overhyped these types of research results to the general public, she notes. "In terms of the benefits of bilingualism, responsible researchers have not actually argued that it produces higher IQ, prevents dementia, or delays old age. Bilingualism does not prevent dementia. Rather, it appears to provide a kind of mental muscle that compensates against the symptoms of cognitive decline, so that bilinguals typically do not present with Alzheimer's type symptoms until they are four or five years older than their monolingual counterparts."

Getting factual information about the science of bilingualism out to the public and policy makers is a mission for Miller and her colleagues. In December 2014, Penn State's Center for Language Science became the first U.S. chapter of the outreach organization Bilingualism Matters

"Our goal is to create a context through which we can celebrate language diversity," says Miller. "By 'language diversity' we mean not only the diverse languages of the world but also the many varieties of those languages, which are often called dialects. Not only are there many bilingual speakers in our community, there are also many bi-dialectal speakers. Just like some languages are stigmatized, some dialects are also stigmatized. Our goal is to bring awareness to the many benefits of being a linguistically diverse person."

For monolingual adults who agree that bilingualism matters, is it too late to reap the benefits of learning another language?

"One of the most important and fascinating findings in the current literature is that it is never too late!" Miller says. "Even late bilinguals, past early childhood, reveal many of these positive cognitive consequences. Likewise, older claims about limits to second language learning, suggesting that adults could not fully acquire the grammar of a second language, have been criticized. New data, especially neuroscience data, show that late learners are indeed able to acquire native-like proficiency."

For younger generations, the growing popularity of dual-language immersion schools is a hopeful trend, she adds. "There is a wonderful documentary about these schools called 'Speaking in Tongues' that we will be screening this summer and fall. There's more enthusiasm for language learning than ever before. Nevertheless, there is more that we can do -- and the programs that are created need to take into consideration the social context of the child."

Says Miller, "For children whose native language is English -- the majority language in our country -- starting a second language early in elementary school is proven to be very important for becoming bilingual. However, when the child's home language is not the majority language, but instead a minority language such as Spanish or Chinese, then programs that not only teach English, but also maintain the home language -- programs with the explicit goal of teaching literacy in both English and the home language -- are the most successful for forming bilingual speakers."

The issue is complex, she admits, "but there are many highly trained bilingual education teachers in our country who have a very solid understanding of the issues involved. They're out there working hard every day to make a difference."

That sounds like good news -- or should we say, buenas noticias, or xǐxùn, or khuśakhabarī, or goda nyheter, or… 

Karen Miller, Assistant Professor of Spanish and Linguistics, can be reached at

Additional resources

Judith Kroll, director of Penn State's Center for Language Science and Distinguished Professor of Psychology, Linguistics, and Women's Studies, was featured on the Diane Rehm Show discussion of the effects of bilingualism on the brain.

  • Karen Miller

    Karen Miller, director of Penn State's Language Acquisition Lab

    IMAGE: courtesy Karen Miller

(Media Contacts)

Last Updated July 28, 2017