I just tried this - even after reading your comment - and my ball was more of an empty space with no color, if that makes sense. So I can see how someone when picturing the scene can still “see” a ball and “see” it rolling, falling, and bouncing but since the prompt never asked about color they simply didn’t choose one and focused on the shape itself.
Exactly. I was more focused on visualizing accurate physics about the object. In that sense it was "vivid". Color simply didn't factor in since it wasn't in the prompt. I can, at this moment visualize complex scenes with color without much issue. Especially after looking up aphantasia more closely, I'm highly skeptical of this test. With that said, I do think I tend to think _without_ color for practical purposes--most of the time I'm just interested in the kinetics of things I'm working through. Otherwise I'm very apt to feel like things have colors about them (my daughter, for instance, has a burnt orange personality; "cosmic" is a yellow word; serene is blue; 118 is red)--so it's not simply having a propensity for not thinking or, more importantly, _feeling_ in color.