Fascinating, and real work. From TEFL contexts, I am told by my partner the distinct linguistic problems different language groups have with english sounds are notorious and very very culture/language specific: Spanish speakers make different pronounciation errors to Chinese and vice-versa, which I think goes to the same place.

But against that, the commonality of the Chomsky grammer model is strong. Doesn't matter what language you speak from childhood, what you develop appears to be part of a larger (universal) comprehension model. So having brain effects differ by language group is .. interesting.

Not to be confused with the headline-grabber "she woke up speaking french" which is a crap pop-sci take on brain issues affecting speech centres, but is totally NOT becoming randomly fluent in french, and no french speaker thinks is french, it just sounds "frenchy" to the anglo-speakers hearing them (or Russian, or whatever: the point is the headline is always mostly the same: she "speaks" some other language)

> the distinct linguistic problems different language groups have with english sounds are notorious and very very culture/language specific

Absolutely, and not just sounds, but also grammar.

Any non-native speaker who knows a lot of non-native speakers with a similar background and likes paying attention to language will be familiar with specific errors that those speakers tend to make. If we learn the other people's native language, we can often even recognize features of their language that contribute to those errors.

I wonder if there's a standardized database that collects these and explains their origins (which seems like something that would be useful for ESL teachers).

> Doesn't matter what language you speak from childhood, what you develop appears to be part of a larger (universal) comprehension model.

Even if we suppose that this is exactly right, it's not necessarily particularly inconsistent with this research. If you damage similar parts of the language apparatus, you could expect the damage to show up differently at the surface level as its consequences propagate to the surface.

Say your functional brain damage makes the ESSS sound difficult for you. In some languages it would be a huge barrier. In others, it might not be. But in a tonal language like Vietnamese, if you lost your musicality, I wonder if you'd suffer different functional loss in your tonal mis-speaks?

I think I get your point, they aren't inconsistent, but it would be odd if different language groups suffered statistically more problems from brain damage than others. I guess the role of language in survival comes to the fore here, we're all well north of its functional need to say me hungrey you pretty but you would think a language with less error survival for brain damage would have not developed as strongly as one with more inherent survivability (assuming language emerged long enough ago it has genetic roots still)

My spanish speaking friend here, who is super-fluent in english continues to call the chocolate-egg holiday of christians "Easters" because its pluralized in Uruguayan-Spanish. My Chinese friends do many future/past tense mistakes because (I am told) Chinese is essentially time-free and you apply modifier words to a sentence in the present tense... Its a wonderful world out there in language folks.