I'd guess few people have much image-like things in their head for data structures or control flows or such. Such can be conjured if one tries to explain something visually by e.g. drawing. But 2D/3D structure is very limited for thinking about abstract stuff like programming.
I don't really have a recollection of or introspective access to what I experience when I focus on something like programming. And I guess many who claim they do are confabulating.