Distinctive features ( Brodmann-1905 ) : compared to Brodmann area 6-1909, area 8 has a diffuse but clearly present internal ganglion cells densely distributed with some granule cells interspersed; the external granular layer ( II ) is denser and broader; cell layers are more distinct; the abundance of cells is somewhat greater.
32.
He described the locus coeruleus, the locus niger ( substantia nigra ) in the brain, in 1786, and the band of Vicq d'Azyr, a fiber system between the external granular layer and the external pyramidal layer of the cerebral cortex, as well as the Mamillo-thalamic tract, which bears his name.
33.
Reelin-expressing cells in the prenatal and early postnatal brain are predominantly found in the marginal zone ( MZ ) of the cortex and in the temporary subpial granular layer ( SGL ), which is manifested to the highest extent in human, and in the hippocampal stratum lacunosum-moleculare and the upper marginal layer of the dentate gyrus.
34.
The term "'area 4 of Brodmann-1909 "'refers to a granular layer ( IV ) such that the boundary between the external pyramidal layer ( III ) and the internal pyramidal layer ( V ) is indistinct; lack of a distinct external granular layer ( II ); a gradual transition from the multiform layer ( VI ) to the subcortical white matter.
35.
The term "'area 4 of Brodmann-1909 "'refers to a granular layer ( IV ) such that the boundary between the external pyramidal layer ( III ) and the internal pyramidal layer ( V ) is indistinct; lack of a distinct external granular layer ( II ); a gradual transition from the multiform layer ( VI ) to the subcortical white matter.
36.
Such requirement of BTG2 in neuron maturation is consistent with the fact that during brain development BTG2 is expressed in the proliferating neuroblasts of the ventricular zone of the neural tube, and to a lower extent in the differentiating neuroblasts of the mantle zone; postnatally it is expressed in cerebellar precursors mainly in the proliferating regions of the neuropithelium ( i . e ., in the external granular layer ), and in the hippocampus in proliferating and differentiating progenitor cells.
