[khazhoux]

Erm... here's a simpler test:

(1) picture a circle

(2) do you see a circle?

(3) do you still see a circle?

Even replace "circle" with "straight line." I think tests like above (balls, people, details) miss the point that in actual aphantasia you literally visualize nothing

[TeaBrain]

I think this hits closer to the mark. For any given description, if a person is able to visualize anything at all, then they don't have the condition. If they do have the condition, then they apparently can't visualize anything.