The impact of bilingualism on the brain: what recent studies say

Bilingualism, once seen simply as a practical or cultural skill, is now considered a real asset for the brain. Recent research in the fields of neuroscience and cognitive psychology reveals that speaking two (or more) languages profoundly influences the way the brain functions. But how does bilingualism really affect our brains? And what are the long-term cognitive benefits?

1. Bilingualism improves cognitive skills

Several studies have shown that bilingualism stimulates essential cognitive abilities, such as working memory, concentration and the ability to solve complex problems. The bilingual brain must constantly juggle between two language systems, which enhances cognitive flexibility. This ability to switch quickly from one task to another (or from one language to another) translates into a greater capacity to manage several pieces of information at the same time, a process known as executive function.

A 2021 study published in the Journal of Experimental Psychology revealed that bilinguals have a greater ability to solve problems under pressure than monolinguals. This cognitive agility enables them to adopt different perspectives more easily, an undeniable asset in contexts as diverse as work, study or even social relationships.

2. Bilingual brains are more resilient to cognitive aging

One of the most fascinating aspects of bilingualism is its role in slowing brain ageing. The brain is naturally subject to cognitive decline with age, but research suggests that bilinguals are better protected against diseases such as dementia and Alzheimer's. A study carried out by the University of Edinburgh in 2020 showed that bilinguals develop the symptoms of dementia on average four to five years later than monolinguals.

The bilingual brain is continually in information management mode, even when the person speaks only one language at any given time. This creates a constant "workout" for the brain, strengthening neuronal connections and maintaining cerebral plasticity, essential for combating the effects of aging.

3. Bilingualism and brain structure

Recent findings in neuroimaging show that bilingualism not only changes the way the brain functions, but also its physical structure. MRI studies have revealed that the prefrontal cortex and parietal cortex (two brain regions linked to the management of complex tasks) are more developed in bilinguals. These regions are called upon whenever the brain needs to inhibit one language in order to use another, which helps to strengthen these specific areas.

A 2022 article published in the Cerebral Cortex Journal confirmed that the volume of grey matter in these regions is higher in bilinguals. Gray matter is crucial for information processing, and increasing its density is associated with better overall cognitive performance.

4. Bilingualism enhances concentration and distraction management

One of the major challenges for the bilingual brain is managing the interference between two languages. For example, when a bilingual has to speak in French, his or her brain must simultaneously inhibit the other language, such as English or Spanish. This requires a great deal of concentration.

This constant management of linguistic distractions results in a better ability to focus on a task, while ignoring irrelevant information. A study published in Psychological Science Journal in 2019 showed that bilingual children performed better on concentration tests than their monolingual counterparts. In particular, they performed better when it came to ignoring disruptive stimuli in a noisy environment.

5. The impact of bilingualism on children: early cognitive development

In children, exposure to two languages from an early age contributes to the early development of executive functions. Recent studies have shown that bilingual children are able to understand complex concepts such as mental flexibility, recognition of different perspectives and empathy at an early age.

Research from 2020 conducted by the University of Toronto revealed that bilingual children develop theory of mind skills faster, i.e. the ability to understand that other people may have beliefs or desires different from their own. This improves their ability to navigate complex social environments.

6. The potential challenges of bilingualism: a cognitive cost?

While bilingualism has many advantages, some researchers point to potential challenges. For example, studies have shown that bilinguals can sometimes have a slight delay in lexical access, i.e. the ability to quickly find the right word in a given language. This is explained by the competition between the two languages in the brain.

However, these slight disadvantages are far outweighed by the long-term cognitive benefits. The effective management of two language systems seems, on the whole, to strengthen rather than weaken linguistic and cognitive skills.

In short, bilingualism offers considerable benefits for the brain at any age. It improves cognitive flexibility, slows brain ageing, and promotes better concentration and distraction management. While it may bring some minor challenges, such as slower lexical access, the long-term benefits far outweigh them. Research continues to explore how bilingualism can contribute to cognitive health, but one thing is certain: speaking two or more languages not only strengthens our linguistic abilities, but our brains as a whole.

If you're reluctant to take the plunge and learn a new language, remember that you're not just communicating, you're also enriching your brain.