>I don't have trouble with a multidimensional array or a graph.

So you can visualize a graph, as if it were drawn out on a sheet of paper?

I can't visualize anything. If I close my eyes, I just see some vague light coming through my eyelids. I can "imagine" for a lack of a better word, the graph and all the nodes and edges "existing", and can reason about its properties based on that.

Would you describe this as similar to proprioception? Like one knows the position of his own limbs without looking or visualizing.