The social cognition of ingroup and outgroup faces: The paradox of categorization and recognition

Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)




Brian Mullen


Social cognition, Ingroup, Outgroup, Faces, Categorization, Recognition

Subject Categories

Psychology | Social and Behavioral Sciences | Social Psychology


Two fundamental processes of human face perception are examined. The history of the study of the categorization and recognition of faces is discussed, as well as possible underlying mechanisms governing these processes. Specifically, prototype and exemplar cognitive representations are posited as the underlying mechanisms by which the categorization and recognition of human faces operate, and evidence suggesting the similarity of mechanism in the two processes is discussed. However, other research is discussed that suggests categorization and recognition operate under different mechanisms. To resolve this apparent paradox between these two perspectives, two experiments were conducted in which participants first categorized faces into two groups and then were asked to recall which faces had been seen during that first task. Participants in Experiment 1 categorized faces into non-relevant, artificial social groups, whereas participants in Experiment 2 categorized faces into relevant social (in- and out-) groups. In Experiment 1, essentially unrelated faces are separated into artificial categories, and no connection between categorization and recognition appears. In Experiment 2, the same faces are separated into categories that elicited ingroup and outgroup processing, and an inverse relationship between categorization and recognition appears for outgroup faces, an effect that is exaggerated by the prototypicality of the faces. Discussion focuses on these differences and addresses factors that may have contributed to these results.