An important component of human social interactions is the ability to infer what other people are thinking about in order to understand others’ behavior. The process of making predictions about the content of other people’s minds, including their mental states (e.g., their beliefs and preferences) is referred to as mentalizing. Mentalizing is crucial for social function and understanding how the brain accomplishes this process can help elucidate some of the questions surrounding the atypicalities in social disorders such as autism spectrum disorder. Mentalizing brain regions include the medial prefrontal cortex (MPFC) and the right temporoparietal junction (RTPJ), but the exact mechanisms that these brain regions contribute during mentalizing remain incompletely understood. This dissertation aims to constrain theory of the potential processes in which brain regions such as the MPFC and RTPJ achieve mentalizing by investigating the kinds of dimensions to which they are sensitive. The first chapter uses a meta-analytic approach to test the hypothesis that MPFC and RTPJ are sensitive to target (i.e., who is being mentalized about) and content (i.e., what is being mentalized about) respectively, while the second chapter further delves into content by using an empirical functional magnetic resonance imaging (fMRI) study examining whether transience can affect recruitment of MPFC and RTPJ regions during mentalizing about others’ beliefs and preferences. Findings indicate that both MPFC and RTPJ respond to transience, but in different ways. The third chapter further looks into MPFC and how thinking about others’ food preferences can have an influence on one’s own personal reported willingness-to-pay for foods. This study suggests that mentalizing could play a role during social influence and that the general presence of social stimuli (i.e., others’ preferences) recruits the MPFC. Overall, the findings from this dissertation point to dissociable roles of the MPFC and RTPJ with the former being sensitive to information about target and stable mental state content, while the latter is sensitive to information about transient mental state content.