BrainInfo

area 4 of Brodmann (guenon)
Acronym: 4

The term area 4 of Brodmann (guenon) refers to a cytoarchitecturally defined portion of the frontal lobe of the guenon. It is located predominantly in the precentral gyrus. Brodmann-1909 regarded it as topographically and cytoarchitecturally homologous to the area 4 of Brodmann (human) and noted that it occupies a much greater fraction of the frontal lobe in the monkey than in the human.
Distinctive features ( Brodmann-1905 ): the cortex is unusually thick; the layers are not distinct; the cells are relatively sparsely distributed; giant pyramidal (Betz) cells are present in the internal pyramidal layer (V); lack of an internal 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.

Also known as: Brodmann's area 4NeuroNames ID : 1014

Size Differences by Sex, Age and Diagnosis

Species Having or Lacking this Structure

All Names & Sources	Internal Structure	Cells Found There	Genes Expressed There
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