Weird. I searched for the definition of Aphantasia and came across this[1] link which describes it in detail. I think I'm the same - I can't visualise things in that way.
[1] - https://www.facebook.com/notes/blake-ross/aphantasia-how-it-...
[1] - https://www.facebook.com/notes/blake-ross/aphantasia-how-it-...
The fact people can actually do this in their minds has blown my mind - metaphorically. I'm genuinely still reeling from this.
(edit: then as a note, you might find this interesting: https://medium.com/@jedgar/my-broken-mind-24bb98a1e793)