Horizontal. But I don't like the terminology; this has much more to do with how well your memory works than with anything spatial. I'm "horizontal" because, lik

Horizontal. But I don't like the terminology; this has much more to do with how well your memory works than with anything spatial. I'm "horizontal" because, like Perry, I find that if I put something where I can't see it then I tend to forget about it and my memory fails to prompt me about it. "Vertical" surely means some combination of having (1) an effective "prompting" memory and (2) some separate system that compensates for any shortfall in #1.