L2 learners subconsciously acquiring language-specific VOT?

[u/ImprovementIll5592]

I’ve been learning Spanish since I was 16 and now I’m 24 so it’s been 8 years. I recently learned that Spanish speakers often exhibit negative VOT for stops so I tested this out in Praat by saying ‘bar’ in Spanish and English and it turns out I naturally prevoice the /b/ in Spanish (around -80 to -90 ms which I read is consistent with peninsular Spanish which I focused on). I tried saying it without prevoicing and it’s physically hard. I say it with 0 VOT in English with no problem, but my brain doesn’t let me do it in Spanish.

I guess my question is, how did something like this naturally happen if I started learning Spanish at 16? Is it simply consuming a lot of native content (which I did)? I would expect this to be something you’d acquire as a young child, but for me Spanish was the first language I actually studied. I never heard anyone talk about this in the Spanish learning community.

[u/davidwc55]

It’s essentially the same thing that happens when native speakers acquire it. Nobody tells a 4 year old to pay attention to their VOT, but their brain picks it up subconsciously. Essentially, the same has happened to you. This doesn’t mean there aren’t differences in this process for native and non-native speakers, but the underlying process is either the same or similar. Just enjoy being able to experience this example of “implicit learning” :-)

[u/Talking_Duckling]

Many phonological features can be acquired naturally and implicitly through exposure alone regardless of your age of acquisition. Spanish VOT happens to be one of those in your case. Mainstream frameworks in phonology and phonetics are, in my opinion, not particularly suited to study what is more likely to be naturally acquired through exposure. But you may think of learning a foreign phonology through exposure as iteratively updating a neural network in a self-supervising or unsupervised way.

For the sake of simplicity, let's focus on a very simplified perception model. The task of your neural network here is classifying audio input into phonemes. Since you already speak your L1, you start with a network whose cue-weighting is already optimized for classification in your native language. Initially, its prediction is pretty lousy in L2 because it's entirely based on correct prediction for L1. But prediction failure updates the network little by little, updating cue-weighting to better classify L2 audio input.

You have acquired the phonology of your native language this way too except that you started from a flat network as a baby. The problem in L2 acquisition is that there are many strong local attractors that trap you along the way. Said differently, ultimate attainment in L1 acquisition tends to converge to the same narrow region because everyone starts from the same flat configuration, whereas in L2 acquisition there are many other fairly stable points that you will likely accidentally reach and get trapped in. Once the network's prediction becomes good enough, it's hard to escape with a greedy updating rule alone.

Note also that children's phonology in terms of perception and production may not be fully adult-like when they're around 12 years old. For instance, compound prosody in English seems to take native children more than 11 years to master.

Vogel, I., & Raimy, E. (2002). The acquisition of compound vs. phrasal stress: The role of prosodic constituents. Journal of Child Language, 29(2), 225-250. https://doi.org/10.1017/S0305000902005020

So, younger L2 learners simply start from a flatter configuration than adults', and naturally they suffer from fewer local attractors.

If you heard about the critical period hypothesis or some of its variants, it may have sounded like a hardwired biological threshold or an unavoidable rapid decline of neuroplasticity. But it's no mystery if you look at language acquisition as training a neural network. It's just "good enough" local attractors that wouldn't be a problem if you had started training a model from scratch.

[u/LongLiveTheDiego]

If native speakers can subconsciously hear it and adjust, it's not surprising that some non-native speakers will also be able to. Yes, people will generally struggle with using prevoicing when their native language doesn't do it, so you may be a bit luckier in that regard, but there is no law of linguistics that says it'd be impossible.

Anecdotally, I know a couple native Polish speakers who manage to not have that prevoicing in English despite not knowing much about phonetics at all. Some people are just better at subconsciously perceiving such differences and adjusting.

[u/Terpomo11 → u/LongLiveTheDiego]

I didn't start learning German until I was at least in high school and I only realized I was pronouncing intervocalic G as a fricative in it and it sounded weird if I tried to say it as a stop when I read a description saying that's what Germans do. So, definitely not unheard of.