Meeting of minds: the medial frontal cortex and social cognition

Social cognitive neuroscience is concerned with the representation of the self, the perception of social groups (such as race and gender stereotypes), and the ability to make inferences about the knowledge, beliefs and desires of the self and of others (known as theory of mind).The results of brain imaging studies have implicated a network of brain regions in social cognition, in which the medial prefrontal cortex (including the anterior cingulate cortex) has a special role.Anatomical studies of the medial prefrontal cortex have revealed systematic differences in connectivity along an axis moving from dorsal through rostral to ventral regions around the genu of the corpus callosum. Functional imaging studies have confirmed this distinction, revealing a progression from motor regions to cognitive and emotional regions.Social cognition tasks engage the central region of this axis, the anterior rostral medial frontal cortex (arMFC). The more dorsal region (posterior rostral MFC, prMFC) is involved in action monitoring and the updating of the predicted value of actions, whereas the more ventral region (orbital MFC) is involved in monitoring reward and punishment, and in the updating of the predicted value of outcomes.Activity in the arMFC is elicited by various social cognitive tasks that have in common the need to reflect on mental states of the self or the mental states of others, including both thoughts and feelings.There is a systematic increase in the complexity or abstractness of representations along an axis from the most superior and dorsal region to the most anterior and rostral region of the MFC. Objective properties of states such as pain are represented in the most dorsal region. The prMFC represents subjective properties, which are re-representations of the objective properties of states. Finally, in the arMFC the subjective properties of states are re-represented, creating metacognitive representations that allow us to think about the subjective states of the self and other people.These meta-cognitive representations are necessary for high level social interactions such as those involving trust, in which we need to have not only self-knowledge and knowledge of others, but also reflected self-knowledge (that is, knowledge of what others think about us).