Knowing two or more languages means that your brain looks and works differently than monolingual brains. Let’s find out what that really means.

Language ability is measured in two active parts (speaking and writing) and two passive ones (listening and reading). Because most bilinguals around the world use their languages in varying proportions, they can be classified into three general types depending on their situation:

Compound bilingual

This is someone who develops two linguistic codes simultaneously starting from a young age. Let’s assume you were born in Peru, but your family decided to immigrate to the US when you were 2 years old. In this situation, you would have learned English and Spanish simultaneously as you start to process the world around you.

Coordinate bilingual

If you have a teenage brother, he might be a coordinate bilingual. He would use two sets of concepts – learning English at school, while still speaking Spanish at home.

Subordinate bilingual

Finally, your parents are most likely to be subordinate bilinguals - they learn a secondary language by filtering it through their primary language.

It’s well known that the brain’s left hemisphere is more dominant in analytical and logical processes, while the right hemisphere is more active in emotional and social ones. Language involves both types of function, while lateralisation develops gradually with age. This leads us to the critical period hypothesis, which suggests that children learn languages more easily because their developing brains have more flexibility which lets them use both hemispheres in language acquisition. On the other hand, in adult brains language is usually lateralised in the left hemisphere. This is why children are likely to be more engaged in the social and emotional contexts of a language, while adults exhibit less emotional bias and a more rational approach when learning a new language.

Read: Native English Speakers Need to Relearn Language

Being multilingual gives your brain some remarkable advantages. This statement would have surprised earlier experts in the 1960s because bilingualism was considered as a handicap that slowed a child’s development by forcing them to spend too much energy distinguishing between languages. Contrary to that, more recent studies show that the effort and attention needed to switch between languages triggered more activity in and potentially strengthened the dorsolateral prefrontal cortex – the part of the brain that plays a large role in executive functions. This proves that while bilingualism may not necessarily make you smarter, it makes your brain healthier, more complex and actively engaged.

Therefore, if you did not have the chance to learn a new language as a child, it is never too late to start strengthening your brain.