Brodmann area Brodmann (1909) area 12 true UBERON:0013543 BIRNLEX:1743 sulcus fronto-orbitalis area praefrontalis UMLS:C1272534 uberon Brodmann area 12 B09-12 area praefrontalis FMA:68609 BA12 UBERON:0013530 area 12 of Brodmann-1909 area 12 of Brodmann B09-12 Brodmann area 12, prefrontal http://braininfo.rprc.washington.edu/centraldirectory.aspx?ID=77 Brodmann area 12 is a subdivision of the cerebral cortex of the guenon defined on the basis of cytoarchitecture. It occupies the most rostral portion of the frontal lobe. Brodmann-1909 did not regard it as homologous, either topographically or cytoarchitecturally, to rostral area 12 of the human. Distinctive features (Brodmann-1905): a quite distinct internal granular layer (IV) separates slender pyramidal cells of the external pyramidal layer (III) and the internal pyramidal layer (V); the multiform layer (VI) is expanded, contains widely dispersed spindle cells and merges gradually with the underlying cortical white matter; all cells, including the pyramidal cells of the external and internal pyramidal layers are inordinately small; the internal pyramidal layer (V) also contains spindle cells in groups of two to five located close to its border with the internal granular layer (IV). Brodmann (1909) area 12 frontopolar area