It may possible be the way we read text. Left to right. At least that's what I have been told by some art studies types. Consequently, in cultures where they read/write right to left (or top to botton), they would have reversed perception of this. There could be mention of this in art theory books, but I am not keen at researching it right now... Checking Japanese, Hebrew & Arabic art might give a clue.
Frantisek
