The term area 12o (macaque) An identifying feature of area 12o is the sparsity of myelination revealed by myelin stain. Features that distinguish it from some adjacent areas are a weakly stained internal granular layer (IV) and lack of sublamination of the internal pyramidal layer (V) ( Carmichael-1994 ). Some authors divide area 12 into only two parts, an orbital part and a lateral part ( Paxinos-2009a ). Its human equivalent is area 47/12s ( Ongur-2003 ), which may be the same as area 47s ( Glasser-2016 ). As granular prefrontal cortex, it has no equivalent in the rat ( Wallis-2012 ).