The whole idea that there's a window that closes when you're a kid has seemed a little weird to me. Adults learn new vocab and grammar all the time. Learning another language is the same, just a little more extreme.
I wonder if there's some actual scientific evidence for the language learning window, and not just some developmental psychology observations.
Perhaps it's just a capacity that some people have, similar to perfect pitch hearing. Possible, but rare.
https://journals.sagepub.com/doi/abs/10.1177/030573561246394...
good thing there's already a drug for that https://www.npr.org/2014/01/04/259552442/want-perfect-pitch-...
science is never fixed is it
I've seen some instances of this, for instance Russians learning French.
My guess is that it's possible if the native language phonemes are a superset of the second language.
In my completely unscientific sampling, I'm going to agree with you. This holds true too for native speakers who make no effort to improve their grammar and vocabulary. If one wants to be a better speaker, writer, and communicator, they will be by effort.
In all my life I've only met two 100% accent-free speakers who learned my language as adults, and a third one who was almost there. Everyone else has something I can detect. But children.. a five-year old Japanese girl could repeat everything I said with perfect pronunciation and intonation, first try. Slightly exceptional girl perhaps, she learned the language in a very short time.
I mean, nobody is disputing "it gets harder as you become older". I totally believe that. Lots of things gradually become harder as you grow older, and language doesn't seem particularly different in that regard. The question is whether that's because your body "cements phonemes in place" around age 12, or whether there's something else at play that's likely gradual and not such a sharp boundary. The fact that it's rare might be just due to the (a) effort required to learn something new being higher in general, or the (b) perceived RoI being lower, or a ton of other factors that don't boil down to "your phonemes are cemented in place"... right? Anecdotally I know in at least one particular case that I observed and inquired about, that person (who's also very smart and hard-working in general) told me they made a very deliberate effort over a handful of years to improve their accent after immigrating, and that's how they sounded like a native now. I totally believe that many people are just unwilling to invest the effort required (which certainly increases with age). I'm just finding it hard to believe there's some biological force preventing you from doing it past age 12, given I've seen otherwise.
> it's more about the brain's ability to hear sounds (my wife can't hear the difference between a number of sounds despite having lived in my country for many years and speaking the language well).
That might be true for some sounds for some people, but I also have a hard time believing it's such a general thing to the extent you're painting it here. It seems more likely to me the explanation is something else, like maybe nobody has managed to give her a good enough explanation as to how they're different sounds. (Maybe not the best example, but I had a hard time distinguishing ch and s in German until someone explained to me how they're each pronounced. Now I can hear them much better, and pronounce them not-too-awfully too.)
But I've also seen this with American and some English adults trying to learn Norwegian - a great many of them can't hear the difference between vowels which, to me, are totally different. Can't hear the difference between the words "har" and "her", for example (NB: Norwegian sounds. Not English vowels). It seems to take a couple of years of daily ear training (or rather, brain training). As always, there are exceptions. But those exceptions are truly standing out.
(Added: As soon as there's context or visibility the problem is much reduced - but it's still there, as soon as there's only audio and their language level isn't good enough to "select" the right words from context).
Similarly in my (learnt as an adult) second language, there are a couple of vowel sounds that aren't in English and I usually have to really focus to hear them, and to pronounce them correctly.
As a native speaker, the sounds in peer/pair/pear/pier are slightly but detectable different. But non-native speakers can almost never say or hear these differences.
There are to main sounds which are in Dutch but not English ([ui] and the hard [G]) and one which isn't in some English dialects (the rolling [R]). However you can absolutely learn them as an adult. It just requires serious training (years of hard practice, same as with sports). You literally have to build up the facial muscles.
One thing I will admit: I choose not to pronounce the [ui] sound properly due to a combination of being lazy, identifying as an Dutch-as-second-language speaker and because for some absolutely irrational it sounds really childish to my years. That latter point played a surprising role in my lack of ability with the French language. It feels theatrical in the way that certain queer people choose to project their speak and I do not want to project as being something I am not (or be confused as someone making crude n-phobic caricatures which would be 1000x worse because it could make someone else feel insulted). Honestly it's probably a tick I have from being raised to be a polite British gentleman :)
And then I wonder which of us is more fluent? The one who with the better accent or the one who can more confidently project their thoughts in that language regardless of "skill"? (Probably the latter)
Professional Actors do it all the time, they spend a lot of time practicing (and I assume money) being trained by Speech Therapists to different perfectly.
Oh man, I hope they sound like this:
I know these languages are all very similar, so that helped a lot for sure, but the 12 years rule is definitely not absolute.
Seems... dubious? What about people who immigrate later (like in high school) and actually pick up the sounds and accents flawlessly? I've seen folks like that and I'm pretty sure they weren't in high school at age 12.