This definitely happens to me, but I did something that kinda fucked my brain up a few years ago. There are times I just can not keep from going into thought loops or zoning out via depersonalization/derealization. And when that happens, the information flow in either direction becomes seriously limited for a time. I'm not around people much anymore, but when I am and it happens, it really sucks because it can even become hard to get words out. Wish I had some work-arounds, but I have none beyond the usual brain health stuff, like healthy diet with right nutrients, good sleep, exercise, and just using it, which you clearly are... damn!

Not to trivialize yours, but it sounds like what you're describing isn't as bad, hopefully that's the case. Regardless, that's awesome and super impressive you're learning languages. I would expect that right there is among the best possible things to do to improve cognition. While not as impressive, for me, getting back into playing guitar and really learning music theory has definitely helped with mental fog stuff. But those 'episodes' still happen.