In experiments starting in 1939, American social psychologists Kenneth Clark and Mamie Clark discovered that black children preferred to play with dolls that were white.

• 在开始于1939年的一连串实验中，美国社会心理学家克拉克夫妇（KennethClark&MamieClark）发现，黑人小孩比较喜欢玩白人造形的洋娃娃。