Bias is perpetuated by conformity with in-group attitudes and socialization by the culture at large. The fact that white culture is dominant in America may explain why people of color often do not show a strong bias favoring their own ethnic group.

Mass media routinely take advantage of stereotypes as shorthand to paint a mood, scene or character. The elderly, for example, are routinely portrayed as being frail and forgetful, while younger people are often shown as vibrant and able.

Stereotypes can also be conveyed by omission in popular culture, as when TV shows present an all-white world. Psychologists theorize bias conveyed by the media helps to explain why children can adopt hidden prejudices even when their family environments explicitly oppose them.