Primate vision, experiments w/ trichromacy

Chinese vs. American visual perception habits

It would be cool, on a related note (it has probably been done, actually) to examine the different perceptions of people who read a r-l language, a l-r language, up-down or multiple directions, when it comes to scanning and analyzing stuff besides words (e.g. just the daily surroundings), and how non l-r readers envision timelines, the past and future, etc.