Brodmann area 8

Human
Brodmann area 8, or BA8, is part of the frontal cortex in the human brain. Situated just anterior to the premotor cortex (BA6), it includes the frontal eye fields (so-named because they are believed to play an important role in the control of eye movements).

Guenon
The term Brodmann area 8 refers to a cytoarchitecturally defined portion of the frontal lobe of the guenon. Located rostral to the arcuate sulcus, it was not considered by Brodmann-1909 to be topographically homologous to the intermediate frontal area 8 of the human. Distinctive features (Brodmann-1905): compared to Brodmann area 6-1909, area 8 has a diffuse but clearly present internal granular layer (IV); sublayer 3b of the external pyramidal layer (III) has densely distributed medium sized pyramidal cells; the internal pyramidal layer (V) has larger 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. The area is involved in the management of uncertainty. A functional magnetic resonance imaging study demonstrated that that brodmann area 8 activation occurs when test subjects experience uncertainty, and that with increasing uncertainty there is increasing activation. (Brain Res Bull. 2005 Nov 15;67(5):403-12. Epub 2005 Jul 7. Variants of uncertainty in decision-making and their neural correlates.Volz KG, Schubotz RI, von Cramon DY.) An alternative interpretation is that this activation in frontal cortex encodes hope, a higher-order expectation positively correlated with uncertainty (Chew and Ho, J Risk and Uncertainty 8(3):267-288. 1994).