by Heidi Stock
A lot has been written about the benefits of bilingualism. So many claims have been made about the benefits of bilingualism that you might think being bilingual makes you better at everything! (It doesn’t.) That said, research shows that being bilingual improves certain brain functions and social skills, and that these benefits extend beyond just speaking another language.
A lot of posts about the benefits of bilingualism don’t provide evidence. I think that leads to readers becoming skeptical about whether all the claimed benefits are real. That’s why I’ve tried to include citations to research studies for every benefit described below. I’ve also included links that let you read the research yourself. Bilingualism really does have benefits from infancy to late adulthood!
As early as possible! As early as pregnancy, babies benefit from hearing a second language. Here’s the evidence:
Babies recognize the differences between languages within hours after birth!
Research shows that babies learn the rhythm and intonation of the language or languages that their mother speaks while pregnant. Amazingly, babies can distinguish their mother’s language from other languages within hours after birth. In other words, the process of learning a language starts early! That is the conclusion of studies conducted by internationally-recognized researcher, Dr. Janet Werker, and her team at the University of British Columbia. For insights into the methodology and findings of Dr. Werker’s lab – and the bonus of adorable baby videos – watch this video.
Babies can hear all human language sounds at birth, but lose this ability over time
According to Dr. Naja Ferian Ramirez, a research scientist at the University of Washington’s Institute for Learning and Brain Sciences, a baby’s brain has an amazing ability: it can hear all 800 sounds – 600 consonants and 200 vowels – that make up all the world’s languages combined. These distinct sounds, called phonemes, distinguish one language from another. At birth, babies can hear all 800 sounds. But gradually, babies lose the ability to hear the sounds that they are not exposed to. Being able to hear a language’s unique sounds is likely one of the reasons that children, unlike adults, can learn to speak a second language without an accent.
Babies’ brains are primed for language learning
According to Dr. Patricia Kuhl, a research scientist and Co-Director of the Institute for Learning and Brain Sciences at the University of Washington: “Science indicates that babies’ brains are the best learning machines ever created, and that infants’ learning is time-sensitive. Their brains will never be better at learning a second language than they are between 0 and 3 years of age.” In fact, research shows that babies as young as 20 months old can learn two languages simultaneously without confusion or delay. According to prominent language-acquisition researcher Dr. Janet Werker: “There is absolutely no evidence that bilingual acquisition leads to confusion, and there is no evidence that bilingual acquisition leads to delay.”
Exposing babies to a language helps them develop “phonological awareness”
“Babies first start learning language by listening not to individual words, but to the rhythm and intonation of the speech stream — that is, the changes between high and low pitch, and the rhythm and loudness of syllables in speech.”
Phonological awareness is the skill of recognizing the sounds and rhythm of a language. Babies start developing this skill before they start learning words. As adults, we can see the space between words as we read, and might think of words as being the most basic building blocks of language. But, there are smaller, even more fundamental, building blocks of language: sounds (or phonemes). As babies develop the skill of phonological awareness, they start to break down the flow of language around them into smaller “units” of language, such as sounds and syllables; they also recognize the “rhythm” of the language. With time, they begin to hear the interplay between sounds, for example, in rhymes (“cat” and “hat”), and alliteration (“bouncy baby”), and eventually they develop the ability to play with those sounds.
Here are 2 fun videos that illustrate phonological awareness of a language. In both videos, there is a speaker who isn’t speaking real words, but is approximating the sound and rhythm of the language.
- This viral video of the toddler and dad discussing the season finale of the show “Empire.”
- A video of legendary comedian Sid Caesar faking four languages.
Exposing babies to a language helps them learn that language later in life
“The earliest traces of a language can stay with us into adulthood, even if we no longer speak or understand the language itself.”
To learn a language, kids need to hear the rhythm of words spoken together naturally. That’s why Whistlefritz’s Spanish and French videos for kids have skits and games where words are spoken in sentences not just single words appearing as “video flashcards” on a screen.
Simply being exposed to the sounds of a language – even if a child doesn’t speak it – provides advantages for learning the language later in life. In one study, Korean infants younger than 6 months were exposed to a language before they had started talking. The infants were adopted, and didn’t hear the language again until they were adults. Despite the passage of time, the infants still had advantages re-learning the language as adults. Why? The study’s authors concluded that the infants’ early exposure to Korean let them develop phonological awareness of the language. As the study’s lead author, Dr. Jiyoun Choi, put it: “Language learning can be retained subconsciously, even if conscious memories of the language do not exist.”
Exposing babies to a second language enables them to adapt better to change
Research indicates that babies raised in bilingual homes are better at flexible thinking. In one study, babies who were raised in monolingual homes and bilingual homes participated in a test. The babies were taught that when they heard a sound, a puppet would appear on one side of a screen. Halfway through the study, the puppet started appearing on the other side of the screen. Only the babies raised in bilingual homes were able to adapt successfully to the change and look for the puppet on the correct side of the screen.
The benefits of learning a second language are myriad. There are obvious benefits – such as being able to communicate with more people and learn about other cultures – but there are less obvious benefits too. Research shows that bilinguals develop stronger cognitive and brain processes that enable them to function better in areas that are both related and unrelated to speaking another language. (See Section 4).
“[B]ilingualism shapes not only language development, but also cognitive development more generally.”
Bilingual children have better “executive functioning” skills
Remarkably, as children learn a second language, they strengthen brain processes and cognitive skills that extend beyond speaking another language. Numerous studies have shown that these brain processes don’t just help bilinguals learn vocabulary, they help bilinguals perform all executive functioning tasks better, including those unrelated to language. For example, learning two languages can improve a bilingual child’s ability to pay attention in math class.
Research demonstrates that bilinguals have stronger skills in the following broad categories of executive functioning:
- Cognitive Skills: Bilinguals have an advantage in cognitive processing tests that involve skills like flexible thinking, paying attention, and ignoring irrelevant information.
- Social Skills: Bilinguals have an advantage in demonstrating empathy, perspective-taking, and theory of mind.
- Language-processing Skills: Bilinguals have an advantage in language-specific skills, including listening skills, vocal recognition, phonological awareness, and learning additional languages.
Here’s the evidence:
Bilingual children adapt better to changes in their environment
One component of executive functioning is flexible thinking; in other words, being able to change what you are doing based on changes in circumstances. Research indicates that bilingual children perform better on tests of flexible thinking. For example, in one study, babies learned that when they heard a sound, a puppet would appear on one side of a screen. Halfway through the study, the puppet started appearing on the other side of the screen. Only the babies raised in bilingual homes were able to adapt successfully to the change.
Interestingly, the bilingual advantage in flexible thinking seems to extend to children with autism spectrum disorder (ASD) as well. Children who are on the autism spectrum typically struggle adjusting to changes in their environments. That’s why recent research conducted with bilingual and monolingual children on the autism spectrum is particularly interesting. In one study, researchers at McGill University asked autistic children between the ages of 6 and 9 to perform tasks that required switching between activities. The study found that bilingual children with autism shifted between tasks more successfully than their monolingual counterparts.
Bilingual children are better at understanding a speaker’s meaning
To communicate effectively, you need to know more than vocabulary; you also need to have the social and emotional skills that allow you to understand another person’s meaning. For example, the word “pop” in the sentence, “I like pop,” could mean “soda,” if the speaker is a Michigander, or “popsicle,” if the speaker is a New Yorker. The meaning depends on where the speaker is from. Reading social cues about meaning – such as where someone is from and how that influences what they might mean – is a necessary part of communication. It’s also something that bilinguals get a lot of practice doing.
In a study conducted by researchers at the University of Chicago, bilingual children and, significantly, children who were exposed to another language though they were not bilingual, were more successful than monolingual children at determining a speaker’s meaning. The study involved a communication test that paired one adult and one child in a game to move objects in a grid. The child could see all of the objects, but the adult could only see some. The child understood that the adult couldn’t see all the objects. For the critical test, the adult asked the child to move the “small” car. The child was able to see three cars – small, medium, and large – but the adult could only see the medium and large cars. To correctly understand the adult’s meaning, the child had to realize that the “small” car that the adult was referring to was the smallest car the adult could see, but not the smallest car the child could see. The adult’s “small” car was the child’s “medium” car. In other words, the child had to understand the adult’s perspective.
As one of the study’s authors, Dr. Katherine Kinzler, explains: “Children in multilingual environments routinely have the opportunity to track who speaks which language, who understands which content, and who can converse with whom. These early social-linguistic experiences could hone children’s skills at taking other people’s perspective and provide them tools for effective communications tools.”
Bilinguals demonstrate greater skills of perspective-taking and theory of mind
The findings of the University of Chicago study – that bilinguals have stronger perspective-taking skills – is consistent with a growing body of research. In two notable studies, researchers tested the difference between monolingual and bilingual children in performing theory of mind tasks. One study involved monolingual and bilingual Persian preschoolers and another involved English and Mandarin monolingual and bilingual preschoolers. Both studies used false-belief scenarios to determine whether the children were able to understand the mindset of another person. In both studies, the bilingual children performed significantly better than their monolingual peers in theory of mind and perspective-taking tasks.
One of the most common ways that researchers test theory of mind skills in children is through “false-belief” tests. To perform a “false-belief” task successfully, a child has to understand that a person can have a belief about something (ex: the toy is in the drawer) that is different than reality (ex: the toy is in the closet). Here’s an illustration of how a researcher could test whether a child, Laura, has an understanding of this concept:
Ben and Laura are in a room. Ben takes his toy, puts it in a drawer, and leaves the room. While Ben is gone, his mother comes into the room and moves the toy from the drawer to the closet. When Ben returns to the room, where will he look for the toy? Even though Laura knows where the toy is, can she predict where Ben will look for it by understanding Ben’s false perspective?
Bilingual children have better listening skills
Being bilingual improves the listening skills of children. In a recent study, bilingual children were able to recognize voices and identify the speaker better than monolingual children. Significantly, bilinguals were able to do so even in languages they didn’t speak.
Why do bilinguals consistently perform better on tests of cognitive and social skills? Researchers hypothesize that the key lies in the brain processes that bilinguals develop to juggle two languages constantly. That process is like body-building for the brain: it strengthens the brain and improves its efficiency. Here’s how:
Research shows that a bilingual person doesn’t have an “active” and a “dormant” language – as was thought in the past – but rather both languages are active all the time. That means that the process of deciding which language to use, and which language to suppress, happens constantly for a bilingual. This process of choosing and ignoring languages is a brain-building workout and it stimulates and strengthens the executive functioning processes in the brain. These strengthened executive functioning processes, once developed, improve higher-level brain function of bilinguals in other areas of life that have nothing to do with speaking a language.
According to Drs. Viorica Marian and Anthony Shook, linguistic researchers at Northwestern University, when a person hears a word, they don’t hear the entire word at once. Instead, they hear the different sounds of the word in the sequence they are spoken. So, before the word is finished, the brain begins to guess what word is coming, by activating words with similar starting sounds. As the experts explain: if you hear “can,” your brain will likely activate words like “candy” and “candle” as well, at least during the earlier stages of word recognition. For bilingual people, the brain will also activate words in the second language that have similar sounds. As a result, the bilingual brain is doing twice the work – like a bodybuilder lifting twice the weight – and that extra work results in stronger brain function.
Surprisingly, even in a situation where only one language is being spoken, the unused language is still active. One way that researchers prove that the two languages are active at the same time (“language co-activation”) is by monitoring people’s eye movements. Because people tend to look at objects as they think and hear about them, where a person looks can reveal what they are thinking.
In one study, researchers compared the eye movements of English-speaking monolinguals to Russian-English bilinguals. The test subjects were asked to pick up an object from a group of objects. When asked to pick up a “marker”, Russian bilinguals not only looked longer at the marker in the group, but also at the stamp, because the Russian word for “stamp” (“marka”) sounds like “marker.” Even though only English was being spoken in the study, Russian remained active for the bilinguals as well.
Learning a second language can delay the onset of symptoms of Alzheimer’s disease. Research has found that bilingual adults start to display symptoms of Alzheimer’s disease about 4-5 years later than monolingual individuals. Even though bilingualism doesn’t prevent Alzheimer’s, bilinguals with more advanced stages of Alzheimer’s can function better for longer. Watch this video excerpt of Dr. Fabrice Jaumont, author of The Bilingual Revolution, interviewing pioneering bilingual researcher and cognitive neuroscientist, Dr. Ellen Bialystok, about bilingualism’s effect on the progression of Alzheimer’s disease. (The full 1-hour interview can be found here).
If you are now panicking because you aren’t bilingual and haven’t started a second language yet with your kids, don’t despair! Most language research is done on people who fit neatly into the categories of “bilingual” or “monolingual.” Typically, studies don’t include people who have some language exposure, but aren’t completely bilingual. However, studies that have included kids with some language exposure have shown positive results, including the University of Chicago study discussed above, as well as a recent study showing that monolinguals who live in communities where they hear other languages spoken have an advantage in learning new languages over monolinguals who don’t hear regularly hear other languages.
Researchers haven’t yet determined what level of language exposure is necessary to achieve all of the benefits discussed above. But, like exercise, some is better than none, and more is better than some. As researcher, Dr. Ellen Bialystok of York University puts it: “The more you use the language, the larger the effects. The more bilingual you are . . . the larger the observed benefit.” So, it’s likely that many of the advantages of being bilingual are also possible for children and adults who aren’t fully bilingual to greater or lesser degrees depending on the amount of language exposure.
Heidi Stock is the founder of Whistlefritz and an un-credentialied nobody in the field of language acquisition research.