A Few More tidbits from Academia: Black is good in Games and Visual complexity and Challenge
In a test in which players were placed with virtual Caucasian and virtual African-American players, Whites generally evaluated African-American players more positively than white players. I can only speculate on the reasons for this, but as a test of social inclusion this shows that online games work towards better inclusion of minorities (and other outgroups) in the predominate ingroup.
In this yeah duh! paper, the researchers find that greater background complexity in a game distracts the player increasing the challenge. What I love is that they suggest increasing background complexity to make games more challenging in places and decreasing it accordingly which is a really clever way of changing difficulty.