An in-depth exploration of the neuroscience of language learning

What exactly happens in the brain when we learn a new language? This is the question cognitive neurolinguistics tries to answer.

More specifically, cognitive neurolinguistics studies “how the brain acquires and processes languages in healthy persons and in pathology.” It may not help you learn Japanese to know that the memory center of the brain is called the “hippocampus,” but knowing a thing or two about how the brain memorizes vocabulary can certainly give you a boost during your studies.

What clues can neuroscience give us on how we can best learn our target language? That’s what we’ll explore in this post.

What part of the brain is involved in language learning?

For many years, scientists believed the left hemisphere of the brain was single-handedly responsible for language learning. In recent years, however, the right hemisphere has been gaining attention as well. The right hemisphere is activated when we identify the basic sounds or phonological elements associated with a language, which is crucial, especially in the early stages of language learning.

“It turns out that the right hemisphere is very important in processing foreign speech sounds at the beginning of learning," says University of Delaware cognitive neuroscientist Zhenghan Qi, who led a study on Mandarin Chinese language acquisition. After the initial stages of learning, the right hemisphere's role “seems to diminish in those successful learners as they continue learning the language.”

Important areas of the left hemisphere include the Broca’s area, in the left frontal lobe, and Wernicke’s area in the left temporal lobe. Broca’s area is responsible for speech production and articulation; Wernicke’s area is tied to language development and comprehension. Generally speaking, grammar and comprehension occur in the left temporal lobe, while auditory processing and vocabulary happen in the temporoparietal lobe. The hippocampus and occipital lobes also support memory and vision in the context of language learning, respectively.

Does learning a language help your brain grow?

A 2019 Swedish study showed that, yes, foreign language learning does have a visible impact on the brain. For the study, young military recruits were exposed to Arabic, Russian, or Dari. Alongside them, another group of participants studied subjects unrelated to language learning over the same period of time. Brain scans revealed that the language learners’ brains grew in size while the other group’s brains did not. Areas of the brain that changed were the hippocampus (related to memory), cerebral cortex, and motor cortex.

Other studies have shown that fluency in more than one language improves memory, cognitive creativity, and mental flexibility. It may also stave off dementia. What’s more, learning a foreign language increases grey matter in the brain, which is densely packed with nerve cells designed to process information. Some more good news: these benefits still hold no matter what age you are when you pick up a new language.

In addition, studies on multilingualism in children show that language learning can enhance working memory capacity regardless of socio-economic background. In other words, memory capacity was correlated with proficiency in known languages, not with kids’ backgrounds.

How do scientists measure language learning?

Cognitive scientists studying language acquisition use a variety of research methods, including EEG, PET, and fMRI, a technique which measures blood flow in different parts of the brain. These methods make it possible to map language acquisition and learning onto specific brain regions, circuits, and processes–and to create computer models of these processes for further study. Different research methods can offer different insights.

For example, a research team at Duke University, publishing data on second language acquisition and multilingualism in the context of a longitudinal fMRI study, was able to confirm previous findings that proficiency is a more important factor in foreign language mastery than the age of acquisition.

On the other hand, legion studies are important because they show us which language acquisition and learning processes no longer function when certain parts of the brain are removed. Together, these methods help shed light on how the brain organizes itself to learn a new language–findings which may influence the way we organize ourselves in our studies.

How does the brain learn a language?

There are some classic language learning techniques rooted in cognitive neurolinguistics, many of which you may be familiar with. For instance, if anyone has ever told you not to cram for a test but to “space your learning” over time, that’s because the brain has an easier time transferring information to long-term memory storage this way.

While cramming may work in the short-term, you’ll find that your memory for the crammed information fades relatively quickly after you take the test compared to information you continually review over time. This is the case for foreign language learning in addition to new information in general.

Associations, contexts and environments

Another tip from neuroscience has to do with association: the more associations you have with a new foreign vocab word, the easier it will be for your brain to retrieve the word from memory when you need it.

This goes for associations in different media (text, audio, tactile) as well as different senses (smell, touch, sound). You’ll also find that your brain loves context when it comes to learning your target language. If you can contextualize a new word (put it in a sentence that can be used in a real-life conversation) or study vocabulary that is personally or professionally relevant to you, your learning will soar.

At Konyang University in South Korea, researchers are studying how the principles of neuroscience can be used to aid adult foreign language learning. They identified four key elements for learning a foreign language in adulthood:

• an immersive environment;
• extensive repetition;
• practicing the language in a variety of contexts; and
• learning in a manner that creates quality copies of the memory.

They note that, in adulthood, using declarative memory (e.g. recalling the name of the 14th president of the U.S.) is more difficult than using procedural memory (e.g. cooking an omelette or tying your shoe) when it comes to language learning. They advise putting in the effort upfront to make grammar and vocab more “procedural,” meaning more automatic, rather than waiting for it to become more automatic over time.

“This process takes more time and repetition and the encoding of these memories is more effective when an emotional stimulus is present,” they write. “There are a variety of techniques that can be used to accomplish this process.”

Stability vs plasticity

Neuroscience can also help explain why it’s harder for adults to learn new languages than for children: the adult brain is biased toward stability as opposed to plasticity, and for good reason–stability allows us to retain the integrated network of things we’ve learned. However, plasticity is important for change and growth.

“When learning a new language, our brains are somehow accommodating both of these forces as they’re competing against each other,” says Matt Leonard, PhD, assistant professor of neurological surgery at UC San Francisco. Using EEG technology, his team was able to identify clusters of neurons in the speech cortex that “fine-tune” themselves as language learners become more familiar with new sounds.

“These are our first insights into what’s changing in the brain between first hearing the sounds of a foreign language and being able to recognize them,” Leonard said in a UCSF press release. “With this study, we were able to see what’s actually happening in the brain regions involved in differentiating sounds during this initial phase of learning.”

There’s an important lesson to be gleaned from the neuroscience of language learning, then, one we can keep in mind as we tackle our next target language: our brains are adaptable, and we can trust them to take on the challenge.

Fun fact: your brain supports you as you learn

Measuring brain activity after a few months of studying a foreign language, researchers at the University of Tokyo found increased activity in areas linked to auditory processing, memory, and grammatical comprehension. As learners became more skilled at their target language, however, activity in these areas decreased.

This suggests that, on some level, the human brain “knows what to do” when it’s exposed to a foreign language, and supplies the resources needed to get the job done. As soon as learning becomes less taxing, your brain doesn’t need to work so hard, so those resources and regions aren’t activated as strongly. However, in the early stages, when we need all the support we can get in navigating our target language, we can count on our brain to step up to the task.

Get to know the neuroscience of language learning

Knowing a thing or two about the neuroscience behind your own language learning may be advantageous for you as you move forward with your studies.

Though it may not help you master your target language to know the names of specific brain regions or methods of measuring brain activity, the results of cognitive studies like the ones mentioned above can offer insight into your own learning process. For more efficient learning, try getting to know your brain a little better.