This is an older thread now but I want to reply here anyway. I think there is a spectrum and some people think visually more than others. It raises the question too of whether some people tend toward visual thinking more as they develop visualisation skills or whether they think throughout their lives in much the same way. It feels to me that I think in concepts, emotions, or visually, and not really in words except for when I'm trying to word something. Thoughts that get to the heart of the meaning happen more quickly and easily than words.
When I think visually, I usually get a hazy 2 or 3 dimensional diagram or image, or sometimes a video. For instance, I can visualise a house with grass on the ground outside of it, trees around it (green and golden brown, like the colours of autumn), fences, and walk through the yard toward the house, and into the house, and my mind fills in the blanks as I go if I will it to. But it's more hazy with occasional flashes of clarity, than persistent. I can leave the thought, return to the thought, etc. I can also think of the concept of a horse and wait for my mind to give me a flash of one, and it might be vague, and I tell myself that's not good enough, and it might give me a picture of a horse almost like a photograph.. only of a photograph I don't recall ever seeing before, and then it's gone. But recalling a visual image of a horse I saw sometime ago isn't something I can easily do.
I think if you don't think visually then your mind compensates by thinking in other ways that serve your needs.