Is It Too Late to Learn a Language Once You Are an Adult?

Recently, I watched a YouTube variety show about the Japanese-language proficiency of Chinese people living in Japan.

All the participants spoke Japanese fluently. They had rich vocabularies and no difficulty holding conversations. But when I listened closely, many still had accents characteristic of Chinese speakers.

One participant said something interesting.

They had lived in Japan since around the age of 13, but said:

“By that age, my brain was already hardwired for Chinese, so my Japanese could not improve any further.”

That was their explanation.

Is that really true?

I have long felt uneasy about this explanation that after a certain age the brain becomes fixed and can no longer acquire a foreign language.

Is It Really Too Late After 13?

Language learning has a concept known as the “critical period.”

Particularly in pronunciation, people exposed to a language from early childhood tend to acquire accents closer to those of native speakers. It is also known that people who begin a foreign language after puberty are more likely to retain an accent from their first language.

I understand that much.

But it is reckless to jump from there to the conclusion that “after 13, you can no longer become good at a foreign language.”

I know someone who came to Japan from China at the age of 16. At least to my ears, their Japanese is indistinguishable from that of a Japanese person. Their pronunciation and conversational rhythm are natural, and even after speaking with them for a long time, I would not realize that they were born abroad.

On YouTube, I have also seen foreigners who came to Japan after turning 20 yet speak remarkably natural Japanese.

By contrast, even setting aside this Chinese participant’s accent, their vocabulary and the logic of their speech were weak.

Why, then, do people who have lived in Japan for similarly long periods develop such different abilities?

Something about the program caught my attention.

The participant’s family reportedly runs a Chinese restaurant.

If the family operates the restaurant together, perhaps they have many opportunities to use Chinese not only at home but also at work. Even while living in Japan, they may spend a considerable amount of time without needing Japanese.

At this point, I realized something. The person I know came to Japan alone. If someone moves to Japan together with their family, would Chinese not naturally remain the language spoken at home?

Of course that would create a difference.

“Living in Japan” and “Living in Japanese” Are Different

Living in Japan for ten years does not necessarily mean using Japanese fully for ten years.

If Chinese is understood both at home and at work, and someone lives within a Chinese community, it is possible to maintain a life centered on Chinese while remaining in Japan.

By contrast, the situation is completely different for someone who comes to Japan at 16 and enters a Japanese high school.

Classes are in Japanese. Casual conversations with friends are in Japanese. Teachers scold you in Japanese. Even romance happens in Japanese.

The people around you will not switch to Chinese simply because your Japanese is poor.

That is powerful.

What matters is not how many years you have lived in a country, but how many hours you have been forced to use its language.

And simply using it is not enough. When people do not understand you, you try again, imitate your friends’ expressions, and correct your mistakes.

It is only natural that after ten years, someone who repeats this learning process every day will be far ahead of someone who uses the foreign language only when necessary.

Do Children Automatically Become Bilingual?

There is a similar misconception in the opposite direction.

“If you take children abroad while they are young, they will automatically become bilingual.”

That is the claim.

Children certainly have an advantage in acquiring pronunciation and distinguishing sounds. But living abroad does not mean that both languages will automatically develop fully.

In an environment where Japanese is spoken at home and English at school, there is still the question of how far each language will develop.

Being able to hold an everyday conversation is different from being able to read abstract writing and write logical prose.

Long ago, I saw a Japanese actress who had spent part of her childhood abroad speaking English on television.

Her pronunciation was extremely natural, and her conversation was fluent. But when the word heritage appeared, she stopped and asked:

“What does this mean again?”

She could not remember the word.

That made sense to me.

Spending childhood in an English-speaking country can naturally develop pronunciation and the rhythm of everyday conversation. But it does not automatically teach vocabulary that never appears in conversations among children.

As you probably know, heritage means something like “legacy” or “cultural inheritance.” It is a standard word in Japanese high school English, but let us not examine that point too closely.

Speaking like a native and using a language at an advanced level are different things.

Some people can conduct specialized discussions and business negotiations despite having an accent. Conversely, perfect pronunciation does not guarantee sufficient vocabulary or writing ability.

We should not confuse the critical period for pronunciation with a limit on language ability as a whole.

Did the Brain Become Fixed, or Did the Learning Stop?

Some aspects of language acquisition certainly become more difficult with age. In pronunciation especially, people who begin in childhood have a major advantage.

But a shutter does not suddenly come down over the brain the moment someone turns 13.

For adult language learners, I think the greater danger is not that the brain has become fixed, but that they stop learning because they tell themselves, “I am too old, so it cannot be helped.”

We cannot easily change the plasticity of our own brains.

But we can change whom we speak with, how much we use the foreign language, and how we correct our mistakes.

Rather than giving up because “my brain is already fixed,” it is better to reconsider your language environment and learning methods.

At least those can be updated at any age.