If anything, I would think there could be slight differences in the dreams, like if a black person(from Africa or something) and a white person(Somewhere north) had exactly the same life, then possibly they could have different dreams... But I don't think it's anymore than that.

Meh, actually, everyone thinks differently, I don't think it's possible to find differences related to the race.

Oh, and ofcourse, /facepalm