Frontopolar cortex shapes brain network structure across prefrontal and posterior cingulate cortex.

Primate frontopolar cortex (FPC), occupied by area 10, sits atop a functional hierarchy of prefrontal cortical regions, yet little is known about its involvement in wider cortical networks. Here we examined resting-state-functional-connectivity (rsfc) in rhesus monkeys with intact or lesioned FPC to identify cortical regions associated with FPC. We present a network of FPC-specific regions of interest (ROIs), whose connectivity was affected by lesion of FPC but not by lesion of neighbouring prefrontal cortex (principal sulcus). This network comprised 'core ROIs' with direct anatomical connections to FPC, located in ventrolateral prefrontal cortex, posterior cingulate cortex, and superior temporal gyrus, and 'peripheral ROIs' well connected to the core network. We further show that the principle effect of a lesion to FPC was to cause a profound disturbance of the functional connectivity of posterior cingulate and ventrolateral prefrontal cortex. We therefore suggest that FPC, posterior cingulate and ventrolateral prefrontal cortex comprise a network of interacting cortical areas whose interactions may be critical for mediating the contribution of FPC to decision making.