Smith, E. R. (1999). Affective and cognitive implications of group membership becoming part of the self: New models of prejudice and of the self- concept. In D. Abrams & M. Hogg (Eds.), Social identity and social cognition (pp. 183-196). Oxford: Blackwell Publishers.

The core insight of social identity theory and related viewpoints such as self-categorization theory is that social group membership is part of a person's self. This assumption has two implications. First, like any aspect of the self, group membership takes on motivational and affective significance. A new theory of prejudice arises from combining this assumption with appraisal theories of emotion. Current models identify prejudice as a negative attitude toward an out-group based on its perceived negative characteristics (i.e., a stereotype) and resulting in attitude-driven discriminatory behavior. Instead, prejudice may be viewed as an emotional reaction to an out-group based on appraisals of its relationship to the in-group (such as threat); discrimination is viewed as emotion-induced behavior. Aspects of this new theory have been tested and confirmed with survey data. If a group can become part of the self-concept, the mental representation of the self, a second implication arises from theories of social cognition. Self/in-group similarity should produce specific patterns of response times, a prediction confirmed by a recent laboratory study. When subjects make judgments about their own characteristics that are inconsistent with the in-group's perceived attributes, they are slower and make more errors. This research illustrates how the integration of social cognition and social identity approaches can advance social psychology, by more closely linking affective and cognitive processes within the individual to the social environment.