Children's Drawings

I found this post today: Children's Drawings Brought To Life and me being the person that I am, I first marvelled at the ingenuity behind translating these children's images into semi-real life, and then went on to marvel at the drawings themselves.

These images are clearly drawn by east-asian - I'm guessing Japanese - children, but if you look at them, they look exactly the same as any image drawn by any child in the 1st world nations. I say the first world, but I have my suspiscions that the style and content of these images would change only superficially between the various nations of our world.

I'm left contemplating if the drawings mark a means of identifying psychological development of the children - is it a universal thing, for instance? Is it dependant on age and gender? Does the wealth of the nation they are brought up in play any part?

I'm pretty damn sure these questions - and more - have been researched, so I think I'm going to go have a look and see what I can find.