[OnACoffeeBreak]

Regarding the follow-up...

I grew up speaking only Russian. I moved to the US when I was 15. I had 7 years of deliberate English practice prior to the move and became fluid in it within a year of moving.

That was about 30 years ago. Because I moved alone, and didn't seek out Russian speakers for this 30 year duration, I only occasionally spoke Russian. The result is that now my Russian feels like a second language. When speaking it, I constantly struggle to translate from English. It doesn't feel like my Russian comprehension diminished, but speaking it is a struggle.

The shift to English being the primary language happened in stages. The last noticeable change for me was when I would need to count something. For a decade, maybe longer, I would default to Russian in my head when counting. The change was gradual, but now it's English all the way.

Fun story... During the first year after the move, I remember being freaked out when I had my first dream where I spoke English.

[rayiner]

I learned English around 5-6, and what’s weird to me is I have vivid memories from before that where I’m speaking English but clearly wasn’t.

[ska]

Memory is a funny thing - much of what we "remember" is created on the fly, based on aggregates. I also have a clear memory from around this age that is impossible.

[Arc_Orion]

Yeah, this is something that I'd love to see research on, though I imagine it might be difficult to find enough people to act as subjects.

That first dream in a target language is always so weird! It's one of those things people say happens when a language first "clicks" for you, but it always feels momentous, even if it happens earlier than expected.

[david422]

> became fluid in it

became fluent in it

I think you want this ^^

When I was in 6th grade I had a classmate move from Canada (speaking French) to the US, and after a couple of years speaking English he said that he started to lose his French speaking pretty quickly.

[OnACoffeeBreak]

Touche... As I was typing that up, I knew I would screw up somehow trying to demonstrate proficiency. :-) Leaving as is.

[jamager]

Language attrition: what we don't practice, we forget. Even the mother tongue.

[simpletone]

> It doesn't feel like my Russian comprehension diminished, but speaking it is a struggle.

I didn't know you could 'lose' a native language that you grew up with til near adulthood. Maybe speaking has more to do with muscle memory and hence easier to lose than a somewhat passive skill like listening and comprehension. Makes me wonder how language is stored and processed in the brain. Are there two complete separate regions for speaking and listening? That feels a bit inefficient.