New research indicates that by the time they are 9 months old, babies are better able to recognize faces and emotional expressions of people who belong to the group they interact with most, than they are those of people who belong to another race. ...While it is plausible that babies would recognize their own race better, they only looked at what white babies do. Maybe white faces are always easier to recognize than black faces. Or maybe faces are easier when they match the race of the baby's care-givers. They study does not say.
In the study, 48 Caucasian infants were given the task of differentiating between faces of their own race and faces that belonged to another, unfamiliar, race. In another experiment, sensors placed on the babies' heads detected brain activity when the babies saw images of faces of Caucasian or African-American races expressing emotions that either matched or did not match sounds they heard, such as laughing and crying.
While 5-month-olds were equally able to distinguish faces from different races, 9-month-olds fared better with their own race. Likewise, brain-activity measurements showed the 9-month-olds processed emotional expressions among Caucasian faces differently than those of African-American faces, while the 5-month-olds did not.
The NY Times has an article on some related research:
In guiding early social leanings, accent trumps race. A white American baby would rather accept food from a black English-speaking adult than from a white Parisian, and a 5-year-old would rather befriend a child of another race who sounds like a local than one of the same race who has a foreign accent.