This answer to the question posed above on Quora, written by Giordon Stark (who was born deaf, and who incidentally has a pretty nice piece on a layperson introduction to the Feynman integral – his standard for “layperson” being pretty high), is pretty interesting:
I was born deaf. I did have speech therapy at an early age, and growing up, my inner voice is figuratively speaking to me and I hear it as well as lipread it. This is the same voice that I imagine people have when they read blocks of text andhear in their head. I don’t exactly see some creepy “Voldemort” face in my head, but I always have some image of lips moving along with a voice that Ihear.
At the same time, I do have memories of when I was little and didn’t speak at all, and all my memories were heavily visual and olfactory. I would always remember specific images of locations and could describe them to my parents in vivid detail trying to figure out what I was remembering. Before speech therapy – my inner voice was highly visual.
Now, as I’m learning/studying sign language in my free time, I’m finding that my inner voice has grown hands as well and I sometimes read things and hear a voice, lip read, and see signs all at the same time. I would expect that a similar experience happens with those who are bilingual/multilingual and sometimes hear all languages at once when reading a text, or perhaps sometimes it switches languages in their heads (although it is a little different because they would hear in whatever language they’re reading in for example).