My dad told me about this article he’d read about a woman who woke up from jaw surgery to find her accent had changed. Interesting… Obviously everyone’s first thought is that her new jaw position is somehow affecting her speech. But there’s probably more to it than that.
Your physical makeup, including your jaw, is definitely important for speech, but it doesn’t actually control your accent. Just think of all the different kinds of jaws people can have even within a small community.
Actually, humans are excellent at compensating for physical differences and coming out with pretty much the same sounds as people around them. Sure, after surgery it might take a while before your muscles get up to speed with their new targets, and you might struggle to relearn certain sounds. But an accent is something much bigger.
An accent is a huge, complex system which governs not only how certain sounds are formed, but which variations of those sounds are acceptable. For example, an English person might pronounce “bottle” with a glottal stop in the middle, [bɒʔʊɫ] “bo’ul”, whereas an Australian or American might use a tap, [bɒɾʊɫ] “borul”. The accent determines which sounds are allowed to substitute /t/. Another thing that can differ between accents is prosody, which includes things like speech melody, how stress falls on certain words (e.g. aluminium vs. aluminium), or even how fast you speak or what kind of voice quality you have (nasal, creaky, etc).
So where did the new accent come from? In this case, it’s something called foreign accent syndrome. Basically after a trauma, your brain somehow blocks your normal accent and makes you speak differently. I remember hearing about a similar phenomenon with one of Sigmund Freud’s patients who forgot her mother tongue after a serious illness, but could still speak other languages. There are also (unverified) reports of people who’ve randomly started speaking languages they never knew before.
The weirdest thing about the woman in the news story was that she was from Texas and had never been further than Mexico, but somehow ended up with a British accent. In this day and age that might not be completely unexplainable, there’s plenty of British people on American TV (I think she sounds a bit like the Supernanny), but it makes you wonder if your brain just stores everything you hear in a secret stash somewhere. I’d be really interested in listening to some longer recordings to hear if there are any features of her old accent still there. Apparently though, it’s slowly started to change, because even though there’s technically “no cure” for foreign accent syndrome, exposure and dialect coaching could help her work her way back to her old way of speaking.