Contributions of the Brain's Mentalizing Network to Inferences about Others' Stable and Transient Beliefs and Preferences

To navigate social environments, people make inferences and predictions about other minds (e.g., their beliefs, preferences, intentions), an ability known as mentalizing. Although the neural basis of mentalizing has been studied extensively, the cognitive processes that support it have been challenging to characterize. One hypothesis is that particular mentalizing processes, subserved by particular brain regions, support inferences about particular categories of mental content (e.g., beliefs or preferences) with defined boundaries. An alternative hypothesis is that apparent categorical distinctions arise from variability along continuous, underlying dimensions. Here, we report evidence that regions of the brain's mentalizing network, including medial prefrontal cortex (MPFC) and Right TPJ, show diverging sensitivity to the underlying dimension of transience, that is, how temporary or enduring the state is that one attributes to another person. During fMRI scanning, participants received information about others and inferred their stable or transient beliefs or preferences in a 2 × 2 design. Overall, the Right TPJ, Left TPJ, and posterior cingulate were more engaged during inferences about transient than stable mental content, whereas dorsal, middle, and ventral MPFCs were more engaged during inferences about stable than transient mental content. Findings support suggestions that MPFC and Right TPJ make dissociable contributions to mentalizing and show that differences in the transience of the mental content under consideration, not only the categorical type of mental content itself, contributes importantly to this dissociation. Results contribute to scientific understanding of the structure of human social cognition, with implications for conceptualizations of atypical social thinking.