The area of visual parts are not equally important, in a particular style, people take part in a selection object of consciousness, as the rest, and graphics as bottom or background.

Researchers using functional brain imagery have confirmed that in such situations the blind person activates not only the parts of the cortex devoted to touch, but parts of the visual cortex as well.

XML documents are all text, but the visual arrangement of parts does not necessarily correspond well to the conceptual connections between the parts.