I'm not sure if you're talking about visualising, but I have a large problem with this. I have virtually no mental pictures especially when reading! I daydream but in the form of words- i.e. I imagine different people talking, but I do not see them talk, I hear them talk. It brings some distinctive promblems in very specific areas of maths, but also some positives, for example, I have a strong auditory memory and can remember many conversations precisely.
I didn't think that was an Aspie thing, because I thought Aspie's had very distinct and strong mental images, but I may be wrong!