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9.5: Growing up bilingual (or multilingual!)

  • Page ID
    • Catherine Anderson, Bronwyn Bjorkman, Derek Denis, Julianne Doner, Margaret Grant, Nathan Sanders, and Ai Taniguchi
    • eCampusOntario

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    One or more interactive elements has been excluded from this version of the text. You can view them online here:

    There’s a bias in the literature on children’s language acquisition: a lot of it focuses on kids who are acquiring just one language, but monolingual kids are not the norm around the world. It is just as common for children to grow up with more than one language in the environment. Some children have one language in the home environment and another at daycare. In some families, one adult speaks one language and another adult speaks a different one. And some kids grow up in an environment where all the adults switch between two or three languages. In Canada and the US, where English has privileged status, it has been common for English-speakers to believe that being bilingual is a disadvantage, or even harmful! Bilingual kids were thought to be less intelligent and at greater risk for developmental delays and so-called “emotional disorders”. Even today in Canada it’s not unusual for a teacher or a doctor to advise parents who speak another language that they should speak English at home so their child doesn’t get confused. This is also the kind of thinking that leads hearing parents of deaf kids to worry that if their child learns a signed language, it’ll interfere with their acquisition of a spoken language. So is it risky for kids to be bilingual? Instead of opinions, let’s look at the evidence.

    Remember that children’s mental grammars develop in response to input from the language environment: whatever language is used by the people around them, that’s the language that a child learns. The amount of language input plays a role in kids’ rate of acquisition. As we saw above, deaf children who don’t have access to language input in a vocal language environment can’t develop a mental grammar for that vocal language. And on a much smaller scale, an only child who is at home with one adult all day might not get a lot of language input and so might not show much language use until they start going to daycare where they get exposed to lots of language in the environment.

    Let’s compare the language environments of two hypothetical children. To make this example simple, let’s say they’re each awake for twelve hours a day, and as long as they’re awake, they’re exposed to language input. The child in the monolingual environment gets twelve hours of Language A every day. The child in the bilingual environments gets, say, six hours of Language A and six hours of Language B: they just don’t get the same quantity of either language as the monolingual child does. So it takes a little longer for them to have encountered enough language to build up the mental grammar for each of their two (or more) systems. In other words, if you measure a bilingual child’s language development in one of their two languages, they might be a little delayed relative to a monolingual child’s development. Their vocabulary in the one language is a little smaller, and it takes them a little longer to reach the typical milestones in grammatical development (Hoff et al., 2011). But that’s only if you compare the one language! If you compare the size of a bilingual child’s vocabulary across both their languages, it’s the same or even bigger than that of a monolingual at the same age (Hoff et al., 2014). So it’s true that there’s sometimes a slight delay in bilingual kids’ development in each of their languages, relative to monolingual kids, when measured using the tests that are standardized for monolinguals.

    But remember that language acquisition is not a race! Reaching a milestone a few weeks later than other kids needn’t be cause for concern. There is a lot of variation between children and between language environments. Some research indicates that the delay is within the normal range of variation for monolingual kids, and some suggests that most bilingual kids catch up to monolingual kids in both their languages by about age ten. In that case, why would there be pressure on parents who have immigrated to Canada to speak English at home? If you think back to previous chapters, it probably has more to do with power and privilege than with children’s development. The stigma associated with non-English languages and with so-called “foreign” accents also extends to children, which means that monolingual teachers and doctors sometimes perceive “problems” in bilingual kids that they don’t notice in monolinguals.

    So the evidence shows us that bilingual kids might have some slight delays in their language development, but these delays aren’t harmful and the kids usually catch up with their monolingual peers eventually. The evidence also suggests that there are advantages to acquiring more than one language. A lot of research has looked at executive function, the set of mental processes that govern your attention and control your impulses. There is a body of evidence that suggests that bilinguals score higher than monolinguals on measures of executive function (Bialystok, 2009; Byers-Heinlein et al., 2017; Peal & Lambert, 1962). The idea is that, when you’re bilingual, your mind is always busy suppressing one language in order to process information in the other language, and this skill transfers to other areas where the mind needs to inhibit irrelevant information to focus on something. I should make it clear that there’s a lot of argument among psychologists and linguists about these effects, because there are so many different ways of defining “bilingualism” and because so many other factors besides language contribute to executive function, but it seems to be the case that being bilingual is one of the factors that can support executive function. If you’d like to learn more about this debate, you might be interested in reading Valian (2015) for a useful summary.

    Besides the executive function research, there’s also evidence that acquiring more than one language shapes kids’ expectations about people. Well before age 1;0, children tend to expect other humans to be cooperative: they show surprise (evidenced by longer looking times) when an adult is trying to reach an object and another adult passes them something different (Vouloumanos et al., 2014). If the adults in this scenario speak an unfamiliar language, 14-month-old bilingual children are still surprised: it seems that they expected the adults’ speech to be communicating a message so they’re surprised at the lack of cooperation. But monolingual children react differently: if the adults speak a language that’s unfamiliar to the children, then the children don’t show surprise when the adult is uncooperative, which kind of suggests they didn’t expect that unfamiliar speech to be conveying any meaningful message (Colomer & Sebastian-Galles, 2020). There’s also recent evidence that bilingual toddlers and preschoolers show less racial bias than monolingual kids on tests of implicit bias and of spoken word recognition (Singh, Quinn, et al., 2020; Singh, Tan, et al., 2020).

    For families who immigrate, one of the most important benefits to raising kids bilingually is retaining the connection to older relatives. Whether or not bilingualism leads to executive function benefits or slight delays in vocabulary size, it’s incredibly valuable for kids to be able to communicate and have a relationship with their grandparents. Overall, there’s no evidence that growing up bilingual or multilingual does harm, while there is evidence that it can be beneficial, and it results in you knowing more than one language, which is pretty neat! If you’re interested in knowing how to support families in maintaining children’s bilingualism, Jürgen Meisel’s (2019) book is useful for non-specialists.

    Check your understanding

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    Bialystok, E. (2009). Bilingualism: The good, the bad, and the indifferent. Bilingualism: Language and Cognition, 12(01), 3.

    Byers-Heinlein, K., Morin-Lessard, E., & Lew-Williams, C. (2017). Bilingual infants control their languages as they listen. Proceedings of the National Academy of Sciences, 114(34), 9032–9037.

    Colomer, M., & Sebastian-Galles, N. (2020). Language background shapes third-party communication expectations in 14-month-old infants. Cognition, 202, 104292.

    Hoff, E., Core, C., Place, S., Rumiche, R., Señor, M., & Parra, M. (2011). Dual language exposure and early bilingual development. Journal of Child Language, 39(1), 1–27.

    Hoff, E., Rumiche, R., Burridge, A., Ribot, K. M., & Welsh, S. N. (2014). Expressive vocabulary development in children from bilingual and monolingual homes: A longitudinal study from two to four years. Early Childhood Research Quarterly, 29(4), 433–444.

    Meisel, J. (2019). Bilingual Children: A Parents’ Guide (1st ed.). Cambridge University Press.

    Peal, E., & Lambert, W. E. (1962). The relation of bilingualism to intelligence. Psychological Monographs: General and Applied, 76(27), 1–23.

    Singh, L., Quinn, P. C., Qian, M., & Lee, K. (2020). Bilingualism is associated with less racial bias in preschool children. Developmental Psychology, 56(5), 888–896.

    Singh, L., Tan, A. R. Y., Lee, K., & Quinn, P. C. (2020). Sensitivity to race in language comprehension in monolingual and bilingual infants. Journal of Experimental Child Psychology, 199, 104933.

    Valian, V. (2015). Bilingualism and cognition. Bilingualism: Language and Cognition, 18(1), 3–24.

    9.5: Child Language Acquisition Bilingualism

    Child Language Acquisition Bilingualism, from Sarah Harmon

    Video Script

    I have referenced several times that most children do not grow up in a monolingual society, that they grew up in at least a multilingual society. In many cases, they grow up in a multilingual household where at least two, maybe more, languages are spoken, and that's not even counting the different dialects. I thought it would be important to have a section talking about bilingualism in children.

    When we're talking about what is considered to be native or quasi-native bilingualism, we’re describing a situation where a child is multilingual from birth, that would be native, or within the first 2-3 years for a quasi-native situation. Some of you are native bilinguals; you grew up in households where more than one language was spoken, or in your society more than one language was spoken. Many of you are quasi-native bilinguals, meaning you spoke one language in the house, and then at a certain point—preschool or kindergarten is usually the start—things change, and then you have to speak a different language.

    Let's talk about that process, a little bit. Historically, in the last 40 years, there have been two main hypotheses with respect to childhood bilingualism. These hypotheses are meant to describe how the child is constructing these grammars in their head and their mental lexicon. Unitary System Hypothesis states that the child initially only constructs one lexicon and one grammar, and then has a word associated with a term from one language or another, but not necessarily both. The evidence for that suggests that young children will only have one term for a given item, so one reference for a given meaning. For example, if a child is a Spanish-English bilingual, and they see this thing (🍼), they're only going to either say ‘bottle’ or ‘botella’; they're not going to say both. There's some evidence for this. The other hypothesis is Separate Systems Hypothesis, which states that the child is constructing one lexicon and one grammar for each language that they're trying to acquire. In this hypothesis, children make the connections along the way. While at times you could argue for either of these hypotheses to explain what happens with native bilingual children, most of the time Separate Systems Hypothesis has more data supporting it.

    The real example of this has to do with children when they are producing language, and specifically as they mix their languages. I'll use English and Spanish as the examples. If you take a Spanish-English bilingual child, and you listen to them talk, you’ll hear them mix, their languages. There's a system to it; they never use the incorrect syntax. They never try to use morphology from one language on lexicon from a different language. You would hear a child say, “I want to go to la playa.” (La playa in Spanish means ‘the beach’.) They do not say, “I want to voy a la playa.” They don't try to mix the morphology and syntax from Spanish in English; they will just use lexicon in the appropriate spaces. If they're talking about ‘the brown dog’, they will say ‘the brown dog’; they will not say ‘the dog brown’, the order of the noun and the adjective in English is the opposite of what it is in Spanish. The child won't mix the order of the of the noun phrase, they will stay in whatever structure is set up for the given language and they do this early on. Whether it is Unitary or Separate Systems Hypothesis that best describes native childhood bilingualism, that we're still not sure of. We tend to lean more on Separate Systems Hypothesis, but there is evidence for both.

    Let's talk about code-switching. In many immigrant societies, code-switching is considered horrible and something to be avoided. Prescriptively, when a child or an adult comes into a formal education or formal setting., they're told they can't code-switch; they have to say in one language or the other but they cannot mix. Here's the reality: code-switching is the best thing that a language learner can do, whether we're talking about a child or an adult. This is particularly true for child language acquisition in multilingual situations. Code-switching shows the amount that the child has acquired in both languages.

    I'll give you a great example. We have a neighbor growing up that, while the parents spoke English, the parents were teaching their children Mandarin because they were Taiwanese. The mother was also a teacher of Cantonese, so she was fluent in Cantonese as well as Mandarin. She was teaching the children Cantonese and predominantly Mandarin as their first language; English was going to come later and they just accepted that. When their daughter was 2-4 years old, she would come toddling down the hill with her family for visit; she would start talking to us in her language. I say ‘her language’ because it was a code-switch of Mandarin and Cantonese, with an occasional English word thrown in there for fun. Of course, my parents and I didn't understand the child, because we speak neither Mandarin or Cantonese, so the mother would have to translate. It was so cute to see how she was putting things together, and how the mother, in particular, would have this question mark on her face, when she could not put the pattern together initially.

    Children will subconsciously code-switch; they're doing as part of spitting out their thoughts. There's no regard for audience; they haven't learned the contextual clues about not speaking a language in front of somebody if they don't understand. As a result, they just blurt stuff out. There are combinations, but those combinations tell us how much they have learned about the respective languages. Adults are different; adults will consciously code-switch, meaning that they do it with intention. They will only preferably do this with other bilingual because they know the stigma of speaking a language that the other person you're talking to does not understand. it's really interesting to see how code-switching develops in a bilingual child; around the age of eight is when they start understanding when and why to code-switch. If you think about a child's development, that is about that time they're starting to learn social mores and norms. Politeness starts really factoring in around that time, so they're starting to put a lot of pieces together.

    The other important aspect to code-switching is consistent input in both languages. If a child has consistent input in both or all of the languages that they speak, they will continue to code-switch and become more proficient at it. But if the input of one of the languages stops, the code-switching also stops, and they start become more monolingual. It can come back, if they go to learn their heritage language. This gets back to contextual knowledge, and this is where semantics and pragmatics come in; a young child isn't going to have that knowledge, because they haven't developed that mentality, nor have they developed neurologically to that point. As they age, things improve. This is all led to the Contextual Knowledge Hypothesis, which is really becoming more plausible when we're talking about bilingualism both in children and adults. It states that as a child reaches that age of about eight, they start intentionally code-switching. It explains a bit about how adults switch between languages—because they're using the contextual knowledge, the environmental cues to know when they can switch. It also explains how listeners go between languages; if you are an English-Spanish bilingual, and I say [si], depending on the context and which language I’m using, that will lead you to understand that syllable, that lexicon differently. If I’m speaking English, and/or if I’m referring to the ocean or the sea, then if I say [si], you're going to think of body of water. If I'm not, and especially if I’m speaking Spanish, then you're going to think of it as ‘yes’, because that is how you say ‘yes’ in Spanish. (It's also how you say ‘if’, but that's another story.) You're using the contextual clues to understand when someone is code-switching; this is both passive and active in its processing, both in receiving/listening to language and when you're producing language. We use parsing to help us with this; we’ll come back to parsing in neurolinguistics in the next chapter.

    It's really important to understand that this is part of what a child acquires if they're in a multilingual environment. It's not just learning the actual lexicon and the morphology and the syntax and everything else. It also ties into the context clues.

    This page titled 9.5: Growing up bilingual (or multilingual!) is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Catherine Anderson, Bronwyn Bjorkman, Derek Denis, Julianne Doner, Margaret Grant, Nathan Sanders, and Ai Taniguchi (eCampusOntario) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.