[Un article de The Conversation écrit par Alejandro Martínez – Personal de investigación en el grupo Neuro-colab, UDIT – Universidad de Diseño, Innovación y Tecnología]
When children grow up hearing two languages, their family and their teachers sometimes worry: will they get confused? Will they take more time to speak? Will this affect their academic results?
These doubts are understandable: indeed, bilingual children can take a little more time to pronounce their first words or mix the two languages at the beginning. However, this is not a pathological delay, but a natural step in their learning. In reality, they treat twice as much linguistic information, which constitutes additional training for their brain, which is reinforced in a very beneficial way for their whole life.
What does it mean to be bilingual?
Being bilingual does not just mean to speak two languages fluently: a bilingual person is the one who regularly uses both languages in his life. This includes those who learn a language at home and another at school, children who speak one language with one parent and another with the other, or those who live in communities where two languages are commonly used.
But are we bilingual forever? The answer is nuanced. A person can stop using one of his languages and, over time, losing it: loss of vocabulary, fluidity or precision. However, even if practical competence decreases, the brain retains the traces of this early learning. Recent studies show that cognitive advantages, such as mental flexibility or the cognitive reserve, even persist in those who have ceased to actively use their two languages.
The bilingual brain in development
During childhood, the brain is very plastic. The hypothesis of the Critical -Guidage period that early learning of languages promotes a more integrated brain organization: the neural networks of different languages overlap and cooperate, instead of functioning separately as is often the case in adults.
For example, a child who learns English and Spanish from an early age being able to pass from one language to another quickly and naturally, while an adult will need more efforts and energy to change language. There are various neuro-imagery studies show that the more a second language is acquired early, the more its neural networks are superimposed on those of the first language, which reduces the effort necessary to change language.
Double learning, without slowdown
In practice, even if bilingual children seem to begin to speak later, they actually distribute their vocabulary between two languages. If a monolingual child knows 60 words in Spanish, a bilingual child can know 30 in English and 30 in Spanish: the total is the same. In other words, they progress more slowly in each language separately, but not in their global linguistic development.
Beyond the vocabulary, the management of two languages from an early age leads to executive control, which includes the ability to concentrate, alternate tasks and filter distractions. For example, a bilingual child can quickly pass instructions in Spanish to those in English in class, or choose the appropriate language according to his interlocutor. These situations strengthen working memory and sustained attention.
The bilingual brain also temporarily removes the language it does not need in each context. This process, known as “inhibitory control”, does not mean “erase” a language, but momentarily deactivate it so that the other can be expressed without interference. This cerebral gymnastics strengthens networks related to decision -making, planning and problem solving.
Benefits throughout life
Bilingualism does not only bring advantages during childhood: its positive effects can last even if, over the years, one of the languages is no longer used regularly. Even if this second language can be lost, early cognitive training continues to act.
For example, the elderly who grew up by speaking two languages have more gray matter in key brain areas and can delay the appearance of symptoms of Alzheimer's disease.
Cognitive flexibility
In addition, mastery of two languages promotes cognitive flexibility, that is to say the ability to adapt to changing situations. When a child or a teenager changes his language according to his interlocutor, reads a text in one language then explains the same idea in another, he exercises his capacity for concentration and attention focused in other contexts: games, conversations in noisy environments, unexpected changes in class or extracurricular activities. This flexibility allows it to acquire new skills more easily.
The conclusion is not that bilingual people are “better” than others, but that their brain learns to manage information differently, which allows them to more easily meet various challenges.
These experiences contribute to the scientists calling “cognitive reserve”, a mental resource that protects the brain and helps maintain cognitive capacities for decades, even in the elderly.
How to take advantage of the advantages of bilingualism
Encourage bilingualism does not mean putting pressure or forcing results, but creating natural exposure contexts to the two languages. Reading stories in two languages, watching films in an original subtitles, singing songs, playing role-playing games or having conversations in a foreign language are informal means of practicing without doing an obligation.
This is important because, even if school programs, such as the Emile method (teaching a material integrated into a foreign language) have a role to play, daily bilingualism is enriched in more spontaneous situations: cooking by following French recipes, playing video games in English or sharing family stories in the mother tongue. These experiences strengthen the emotional link with language and make it a living tool, beyond school.
Far from being a challenge, exposure to two languages is an opportunity for children to develop a flexible brain, well connected and capable of effectively organizing knowledge. Growing up in contexts that value the two languages makes it possible to take advantage of these cognitive and cultural advantages, by supporting both their school learning and their personal development. 
With an unwavering passion for local news, Christopher leads our editorial team with integrity and dedication. With over 20 years’ experience, he is the backbone of Wouldsayso, ensuring that we stay true to our mission to inform.
