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refers to a cortical area in the parietal lobe defined on the basis of cytoarchitecture in the rhesus macaque (Macaca mulatta). The author regarded it as the same as area 7 of Brodmann (guenon). The cortical thickness was 1.80 mm. It was distinguished from area 5 of Peele particularly by 1) a lack of large pyramidal cells in the internal granular layer (V); 2) by a radial arrangement of cells in the supragranular layers I, II and, especially, III, which the author likened to the pattern seen in area 6 of Brodmann (guenon) in the frontal lobe; and 3) a stripe formed by slender triangular shaped pyramidal cells in the innermost sublayer of layer III. The molecular layer of the cerebral cortex (I) was wider than in the postcentral gyrus and contained only a few spindle cells and granule cells. The external granular layer (II) contained medium sized granule cells that were less densely distributed in a narrower band than in area 5 of Peele; its boundaries were indistinct. The external pyramidal layer (III) had three distinct sublayers with pyramidal cells, very many triangular in shape, that progressed from smaller to large in the deepest of the three sublayers; it differed from that of area 5 of Peele in that the cells were not as densely distributed, and the larger cells were not as large as in area 5. The internal granular layer (IV) was 12 to 15 cells thick and was of very small granule cells less densely distributed than in area 5. The internal pyramidal layer (V) was ill-defined and contained medium to large pyramidal cells. The multiform layer (VI) was compact, had a distinct boundary with the underlying white matter and contained small pyramidal cells and spindle cells ( Peele-1942 ).
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