The term area 8 refers to an area defined by internal structure posteriorly in the superior frontal gyrus and middle frontal gyrus. Identified on the basis of multiple stains in the human, it is bounded rostrally by area 9 and area 9/46, caudally by area 6. It extends onto the medial surface of the superior frontal gyrus where it is bounded, approximately at the cingulate sulcus, by area 24 and/or area 32ac, depending on the author. On the lateral surface it is bounded caudoventrally by area 44. It has two subdivisions: area 8A and area 8B. Architectonically it is part of the dorsolateral prefrontal cortex, which is perhaps the most variably segmented part of human cerebral cortex ( Zilles-1990 ). In this segmentation it is one of four parts. The others are area 9, area 9/46, and area 46 ( Petrides-2012 ). Its equivalent in the macaque is similarly located ( Petrides-2009 ). As granular prefrontal cortex, it has no equivalent in the rat ( Zilles-2012 ).