Native language is specially stored in the brain for easy access

Imagine someone who can effortlessly switch between chatting with their grandma in Italian and arguing philosophy with a classmate in French. That’s a polyglot, someone who can speak multiple languages. 

A new MIT study explores how their brains handle this impressive feat. The experts found that while the brain’s language network lights up when processing any language, it works less intensely for a polyglot’s native tongue. This suggests our first language becomes specially encoded in the brain, allowing for smoother comprehension.

Unique language processing

The researchers, following up on prior work on polyglot brains, delved deeper in this study. The central question: how does fluency affect the brain’s processing of different languages? 

To investigate, the experts recruited 34 polyglots that spoke at least five languages. “With polyglots, you can do all of the comparisons within one person. You have languages that vary along a continuum, and you can try to see how the brain modulates responses as a function of proficiency,” explained Professor Evelina Fedorenko.

Using brain scans, the researchers monitored brain activity while participants listened to passages in eight different languages. This included their native tongue, languages with varying levels of proficiency, and even completely unknown languages.

Easier processing of the native language

Scientists found that the brain processes our native language much faster and easier than other languages. The key to this is early learning.

We typically learn our first language very young, during a special time called the critical period for language. This is when our brains are extra good at picking up languages. 

We soak in all the rules and words like sponges. Because we’re exposed to this language so early and all the time, it becomes ingrained in our brain’s language areas.

Specific pattern of brain activity

Scientists could actually see this happening in the brain scans. When people listen to their native language, there’s a specific pattern of brain activity. 

Parts of the brain linked to language, like Broca’s area for speaking and Wernicke’s area for understanding, light up less. Basically, our brain has a special shortcut for processing our first language, making it faster and easier to understand and speak.

Processing additional languages

The researchers found that for languages someone just started learning (beginners), understanding and speaking require more effort. This activates a wider range of brain regions, including some not typically involved in language processing. These extra areas might be related to memory, focus, and problem-solving, which are all needed to grasp a new language.

As someone gets better at a language, the brain becomes more efficient. It starts using specific pathways dedicated to language processing, similar to those used for the native language. 

However, even at this intermediate level, the brain still uses more effort from the areas that control complex tasks to manage the challenges of a language that’s not fully mastered.

“As you increase proficiency, you can engage in linguistic computations to a greater extent, so you get these progressively stronger responses,” said Dr. Fedorenko.

“But then if you compare a really high-proficiency language and a native language, it may be that the native language is just a little bit easier, possibly because you’ve had more experience with it.”

Exposure to unknown languages

Even if the listener can’t understand the content, unknown languages still activate parts of the brain network responsible for language. This includes areas that process speech sounds and try to decipher any potential language structures. 

Our brains are naturally wired to search for patterns and meaning, so they automatically attempt to break down and comprehend speech sounds, regardless of familiarity.

Interestingly, exposure to unknown languages can also activate areas related to both hearing and sight. This is especially true if the listener tries to associate the heard language with written forms or visual contexts. 

The brain seeks any available clue to aid in understanding, demonstrating its flexibility and the integration of different senses in cognitive processing.

Future directions

The current research focused on polyglots who started learning additional languages during their teenage years or adulthood. However, future studies aim to explore a different group: individuals who were exposed to multiple languages from a very young age. 

Additionally, the researchers plan to investigate a group that learned one language in infancy but then immigrated to the United States at a young age. This group primarily uses English, leading to a decline in their native language proficiency. 

By comparing these groups, the researchers hope to isolate the impact of language proficiency on brain activity from the influence of acquisition age.

The study may also offer valuable insights into cognitive development, potentially aiding in diagnosing and treating language-related disorders.

The study is published in the journal Nature.

—–

Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.

Check us out on EarthSnap, a free app brought to you by Eric Ralls and Earth.com.

—–