Scientists explain why learning a new language is so difficult

The brain lives in a state of constant flux. It repeatedly adjusts to improve our mental performance while juggling millions of incoming signals. While this adaptability keeps us convincing, scientists say this is precisely what makes it so difficult for adults to learn new languages.

The activity of brain cells can be divided into two categories: plasticity and stability. Plasticity refers to the brain’s ability to change. As we get new information, we form new connections between neurons. Stability is the opposite; it allows the brain to hold on to things that we have already learned, to make those connections hold.

Young children have a high level of “neural plasticity”. Forming new neural connections is helpful for children as they need to learn tons of new information and discern what is important enough to hold onto. But as we age, the brain’s ability to make new connections naturally decreases. Neuronal plasticity decreases.

“The brain begins to prioritize stability,” said Matt Leonard, assistant professor in the department of neurological surgery at the University of California, San Francisco. “We basically want to hang on to the important things that we have spent the last decade or more learning.”

When learning a new language, humans rely on plasticity, according to new research published Monday in the Proceedings of the National Academy of Sciences. This is why children can often learn several languages ​​with little effort, while adults tend to have difficulty understanding a few lessons from Duolingo.

To understand how the brain might pick up a foreign lexicon, neuroscientists at UCSF studied the brain activity of 10 English-speaking epilepsy patients while the subjects learned Mandarin. These volunteers already had electrodes in their brains due to their condition and agreed to extend data from the devices to the project, providing a unique opportunity for researchers to directly study the human brain as it learns.

After completing the analysis of the subjects’ brain data, Leonard and his fellow researchers found that the “buttons” of neurons – in the region of the brain known as the cortex of speech – were active during the learning process. . This means that some neurons did not participate.

“There are different types of groups of neurons, some of which seem really ready to change with learning and others that are more resilient,” Leonard said.

He notes that the team chose Mandarin as the “new” language for the study because its sounds contrast sharply with the cadences of English. This makes learning more difficult for English speakers, as it forces them to form a large number of new neural connections.

Our brains are more likely to pick up familiar sounds, another reason to surround ourselves with a language is often more effective than formal lessons. It all has to do with training our brains to recognize patterns and engage our neurons.

“The best way to learn a new language, whether you are a child or an adult, is to immerse yourself in it,” said Leonard, “to be surrounded by native speakers as much as possible.”

He also points out that during any learning process there will be ups and downs. In fact, data on the brain activity of the study subjects indicated large variations in learning success.

“There might be times when the stability neurons have kind of turned off and they might just be like, ‘Look, we need to slow this down and not change things up too much just yet,’” Leonard explained.

But when the going gets tough, the key is to stay motivated. It might be in our best interest to continue our French lessons motivated by the COVID-19 containment, even if the only word we can say with any semblance of confidence in a few months is Hello.

“If you are learning,” said Leonard, “and you start to say to yourself,” I wanna not understand, I’m starting to lose what I’m supposed to be careful about, “and your motivation decreases, you are not going to do as well. “