Automated sub-sub conscious processors in the brain are mostly responsible for how little information the higher mind has to deal with. If there is a tree in a movie, the visual cortex will say "It's a tree, what next?". If there is an abstract tree symbol, the visual cortex will say "What is this giant solid color block sitting in the middle of my field of view?" and send it up to your conscious mind for processing, resulting in a more taxing experience for the audience. Of course, if we knew how the brain worked, we could maybe somehow send signals directly to whatever ball of neurons handles abstract concepts...