As Max mentioned, I have aphantasia, as well as prosopagnosia. So I don’t visualize things, and I can’t really recognize faces. I have extremely poor scores on tests of visuo-spatial ability, such as free rotation of objects, or pattern extending/recognition, or even simple tasks like orientating one’s self appropriately with regards to cardinal directions, or my left and right side. Very badly physically coordinated as well.
I compensate for this inability to identify people by their face by having a keen ear for people’s voices, and noticing small details about them that I can hopefully try to puzzle together to identify them correctly. Big ones are voices, gait, hair style, perfume/cologne, and clothing choices- the weight and draping of fabric, for example, or if someone wears a signature item often. The constant mental cataloguing of facts about people makes for easy material to pick from while writing, but you also notice trends that can sometimes deeply unsettle people: like when I surprised Pinkz with the rhubarb pie anecdote.
Back when I was in highschool, dad would come to pick me up sometimes- driving the same car he always had. I was always careful to look for it- it was an old, modded out (dropped low) car that stood out like a sore thumb against the backdrops of soccer mom SUVs and gleaming pick up trucks. But if I didn’t see it, and he parked a little further down the street, I wouldn’t recognize him even if he was the only man walking towards me, in broad daylight and full view, until he opened his mouth to call for me. I could recognize his voice anywhere- but even looking at him dead on, I was never quite sure if it was him until he spoke. He thought I was daydreaming, most of the time, though once he realized I literally did not know who he was, he made it a habit to play one of his favourite songs and to call for me by name instead of just jogging and waving an arm to flag me down.
The thing that trips up some people is the fact that I don’t… see anything, when asked to visualize. But I still know like, stuff about things. I can’t see an apple, but I could describe one fairly well enough, because instead of a picture, it’s a bit like a museum plate or tag listing off a description. (I don’t see the text. But I just know that like, apples are usually red, and have smooth skin, and sometimes mealy pale flesh, if they’re not particularly good. And so on.) This impacts my art, too, since I’m a visual artist: I need to use a lot of references, build up muscle memory, and also sometimes still do strange things like fully render pieces but shear off fingers, place thumbs on backwards, or completely mangle symmetry because I don’t notice it looks weird. Also makes me pretty prone to same face syndrome for my characters. But I can paint very, very well from life studies, because I never struggled with the issue some artists have of ‘drawing what they think they see, rather than what they see.’ I just don’t often do them because I find it a bit boring.
I think mostly in my own voice, as if I were narrating everything in my head. No visualizations. I can, however, ‘think thoughts’ with other people’s voices: particularly if I’m reading messages from them, (though the default narrator for things like books, is my own voice), or if I think about ‘well what might daddy say if I asked him about what I should do?’, then I can think of what I think he might say, and have ‘his voice’ say it. And I can conjure the memory of what things smell or tasted or felt like in pretty high fidelity: which means food cravings really hit hard, sometimes…
I was incredibly jealous when I learned that Manon and Pinkz see things when they read- a bit like movies, or television. I love reading, but I don’t get that experience: it’s just the page in front of me, my internal narration, and that’s about it. I do think this makes editing easier for me though, (apparently he often is distracted by the visuals), and makes it easier for me to remember specific phrases because I focus so much more on the language. I also don’t have a visual image of like, an idealized form of what I’m trying to draw, so I don’t feel the emotional despair of dissonance between what you’re trying to draw, and what you can draw, that apparently plagues a lot of artists. I think not having to deal with that emotional hurdle made it a lot easier for me to pick up painting. And it definitely forced me to learn how to use words to describe things, which is why despite not being able to visualize, my writing is so full of visual comparisons and imagery.