The cerebral cortex of humans and nonhuman primates is separated into a frontal and posterior region by the Rolandic fissure. The primary motor cortex (area 4) is a relatively narrow cortical area that lies immediately anterior to this fissure, and immediately anterior to the primary motor cortex is the premotor cortex (area 6). The PFC makes up the remaining anterior pole of the frontal cortex (Fig. 1, shaded area) and is divided into three interconnected subregions known as the lateral PFC, the medial/cingulate PFC, and the orbital PFC (commonly referred to as the orbitofrontal cortex (OFC)). Although overlapping but not identical, the term ventromedial PFC is sometimes encountered in the literature instead of OFC.
