Figure 1.

The social brain: from structures to networks. (a) Structures. There are a number of brain regions, only a subset of which are depicted here, that are now known to be involved in social cognition. Some of these are implicated because damage to them impairs aspects of social cognition and behavior; others are implicated because they are differentially activated in healthy brains when people perform social tasks in an MRI scanner. TPJ, temporoparietal junction; dMPFC, dorsomedial prefrontal cortex; STS/STG, superior temporal sulcus/gyrus, FFA: fusiform face area; vMPFC/OFC, ventromedial prefrontal cortex/orbitofrontal cortex. (b) Networks. Several core social cognition networks have been described. Not surprisingly, most of these encompass structures from the original ‘social brain’ [see Panel (a)], although a few new ones have been added, as well. We outline four here. One is a network centered on the amygdala [62,64,135]; the functions of this network (which will likely fractionate into several that are linked to specific amygdala nuclei eventually) range from triggering emotional responses to detecting socially salient stimuli to social affiliative behaviors. A second is the so-called mentalizing network, a collection of structures correlated at rest and activated by thinking about the internal states of others [29,136,137]. A third is recruited when individuals empathize with others [138,139]. A fourth network is activated during observation of the actions of others, including their emotional expressions [28,140,141]. Please note that, for simplicity and clarity, not all regions implicated in the networks are shown; several networks also involve other subcortical and brainstem structures not illustrated here.