One of the biggest concerns that parents have about raising children in a bilingual household is that it will cause confusion. But is there any scientific evidence that young bilinguals are confused? The first question to ask is what confusion would look like. Except in the case of neurological disorders (Paradis, 2004), fluently bilingual adults can speak whatever language they choose in the moment, and are clearly not confused. But what about bilingual children and infants?

One misunderstood behavior, which is often taken as evidence for confusion, is when bilingual children mix words from two languages in the same sentence. This is known as code mixing. In fact, code mixing is a normal part of bilingual development, and bilingual children actually have good reasons to code mix (Pearson, 2008). One reason some children code mix is that it happens frequently in their language communities—children are just doing what they hear adults around them do (Comeau, Genesee, & Lapaquette, 2003). A second reason is that, just like young monolinguals, young bilinguals are sometimes limited in their linguistic resources. Similarly to how a monolingual 1-year-old might initially use the word “dog” to refer to any four-legged creature, bilingual children also use their limited vocabularies resourcefully. If a bilingual child does not know or cannot quickly retrieve the appropriate word in one language, she might borrow the word from the other language (Lanza, 2004). Rather than being a sign of confusion, code mixing can be seen as a path of least resistance: a sign of bilingual children’s ingenuity. Further, bilingual children do not seem to use their two languages haphazardly. Even 2-year olds show some ability to modulate their language according to the language used by their conversational partner (Genesee, Boivin, & Nicoladis, 1996). There is also evidence that children’s early code mixing adheres to predictable grammar-like rules, which are largely similar to the rules that govern adults’ code mixing (Paradis, Nicoladis, & Genesee, 2000).

What about bilingual infants? Again, the research is clear: bilingual infants readily distinguish their two languages and show no evidence of confusion. Languages differ on many dimensions—even if you don’t speak Russian or Mandarin, you can likely tell one from the other. Infants are also sensitive to these perceptual differences, and are particularly attuned to a language’s rhythm. Infants can discriminate rhythmically dissimilar languages like English and French at birth (Byers-Heinlein, Burns, & Werker, 2010; Mehler et al., 1988), and by age 4 months they can tell even rhythmically similar languages like French and Spanish apart (Bosch & Sebastián-Gallés, 1997, 2001; Nazzi, 2000). Bilingual infants may be even more sensitive than monolinguals when it comes to discriminating languages. Recent research has shown that 4-month-old monolingual and bilingual infants can discriminate silent talking faces speaking different languages (Weikum et al., 2007). However, by 8 months of age, only bilinguals are still sensitive to the distinction, while monolinguals stop paying attention to subtle variations in facial movements (Sebastián-Gallés, Albareda-Castellot, Weikum, & Werker, 2012; Weikum et al., 2007). Instead of being confused, it seems that bilingual infants are sensitive to information that distinguishes their languages. Сократи этот текст оставив только важную информацию