As someone who lost their tongue in a freak hotdog eating accident, I can confirm this is true.

I had to get a new robot tongue and it's not as effective. But with practice, you make out the sounds you need.

Archive link, for those who are paywalled.

The text is interesting, and it confirms a suspicion that I had that L1 is not written in stone, or that your languages are not like a swamp ogre, full of layers. I wish that I could contribute more to this topic but language acquisition and attrition is rather far from my "turf".

Duh.

I lived in Germany for two years, and when I returned I visited the mother of one of my high-school girlfriends who'd been living in the States since she'd moved there from Germany when she was 20. So, she was around 40 at the time. Anyway, me, fresh from DE and pretty fluent in German tried to have a conversation with her in German and, after a couple of minutes she switched to English and said, "I'm sorry. I've just forgotten too much German to have a conversation in it." She seemed sad about that.

But oddly, the reverse had been happening to me off and on since I'd gotten back. I'd been living with a German girl over there who didn't know much English, and I hadn't spoken English much in the past 18 months. For about a year after I returned I'd occasionally be unable to remember the English word for common things, like "trash can," and have to ask whoever I was talking to to remind me what it was.

Doesn't take much, honestly.