Can Adults Learn Languages Like Children?
A common hypothesis among the linguistics community is that children learn languages much more easily and quickly than adults.
Supporters of this hypothesis indicate that children have more of a “clean slate” during the first few years of their life.
On the other hand, adults already speak and communicate in their native language, which diminishes their busy minds’ learning capacity.
The critical period hypothesis is the formalization of this debate. It links the ability to acquire a language to aging. The more you age, the hypothesis asserts, the less capable you are of picking up a language.
Here is Tom Scott explaining the critical period hypothesis:
This hypothesis was developed many decades ago, yet there is still scientific debate as to whether it is true. In other words, it remains an open hypothesis.
The fundamental question is, how do children learn a language, and how does this differ from the ways adults do the same?
There is no scientific answer here, there is a basic truth that sheds light to why this remains an open question.
Children, particularly early in their life, tend to learn from their surroundings, more so than adults.
Bi-lingual children can pick up a number of different languages at the same time, as they grow up. But that is without necessarily realizing that they’re speaking different languages.
Here’s Noam Chomsky:
It’s just: This is the way you talk to your aunt, this is the way you talk to your father, and so on and so forth. In fact, it’s been recently shown that children who live in bimodal environments–that is, where one parent speaks, and the other parent uses sign language–pick up both languages with apparently no preference. It’s just like learning both English and Japanese.
The major issue with this debate is that you cannot draw a valid comparison between adults and children acquisition ability without controlling for their acquisition method.
And the fact is, many children in the world acquire their second (or third, or fourth) language from their surroundings (parents, friends, language school, etc.), whereas most adults learn the same via methods that merely aim to improve memorization (flashcards, dialogues, grammar books, etc.).
These fundamentally different methods make any comparison between children and adults’ acquisition ability moot.
The real question to ask is…
Do we observe differences in language acquisition speed and aptitude between adults and children who learn a foreign language via an immersive method (e.g., living in a different country, heavily interacting with native speakers)?
Admittedly, I don’t know. But I would bet that such differences prove to be minor (unless we are talking about seniors, of course).