I have been following stories about aphantasia with interest because I am 99% sure I have it. Carl Zimmer reports in The New York Times:
Dr. Adam Zeman didn’t give much thought to the mind’s eye until he met someone who didn’t have one. In 2005, the British neurologist saw a patient who said that a minor surgical procedure had taken away his ability to conjure images.
Over the 16 years since that first patient, Dr. Zeman and his colleagues have heard from more than 12,000 people who say they don’t have any such mental camera. The scientists estimate that tens of millions of people share the condition, which they’ve named aphantasia, and millions more experience extraordinarily strong mental imagery, called hyperphantasia.
When I read a book, I never think about what the characters look like, or what the scenery is.
When I think, it’s all words. Torrents and torrent of words.
I don’t have the best visual memory for people or places, though I have good spatial awareness.
I think I can form mental images, or at least simulacra of them (wireframes, maybe). I mean, I did pretty well in organic chemistry in college, which is a subject that is, in part, about visualizing the rotation of irregularly shaped molecules. I don’t think I saw them in my mind’s eye, though. Not really. It was long ago, so I can’t remember reliably, but I probably figured out a different way to do it.
To me, it is interesting to learn that some people “see” mental images easily and think in an incredibly visual manner, because that is not the way I experience anything.