Dissociable neural correlates of stereotypes and other forms of semantic knowledge.

Semantic knowledge refers to the information that people have about categories of objects and living things. Social psychologists have long debated whether the information that perceivers have about categories of people--i.e. stereotypes--may be a unique form of semantics. Here, we examine this question against well-established findings regarding the neural basis of semantics, which suggest that two brain regions--left inferior frontal gyrus and inferotemporal cortex--are critical for general semantic knowledge. During functional magnetic resonance imaging, participants answered questions about their knowledge of both non-social and social categories. We reasoned that if stereotypes are a typical form of semantic knowledge, then these same regions should subserve the activation and retrieval of stereotypes. Inconsistent with this possibility, left inferior frontal gyrus and inferotemporal cortex were activated only during non-social category judgments. Instead, judgments of social categories were associated with regions frequently linked to social cognition, including medial prefrontal cortex, posterior cingulate, bilateral temporoparietal junction and anterior temporal cortex. Together, these results suggest that social stereotypes should be considered distinct from other forms of semantic knowledge, and may have more in common with representing mental states than retrieving semantic knowledge about objects and non-human living things.