Spatial organization of neurons in the frontal pole sets humans apart from great apes.

Bibliographic Collection: 
MOCA Reference, APE
Publication Type: Journal Article
Authors: Semendeferi, K.; Teffer, K.; Buxhoeveden, D. P.; Park, M. S.; Bludau, S.; Amunts, K.; Travis, K.; Buckwalter, J.
Year of Publication: 2011
Journal: Cereb Cortex
Volume: 21
Issue: 7
Pagination: 1485-97
Date Published: 2011 Jul
Publication Language: eng
ISSN: 1460-2199
Keywords: Adult, Aged, Animals, Biological Evolution, Female, Frontal Lobe, Gorilla gorilla, Hominidae, Humans, Hylobates, Male, Middle Aged, Nerve Net, Neurons, Pan paniscus, Pan troglodytes, Pongo, Species Specificity, Young Adult

Few morphological differences have been identified so far that distinguish the human brain from the brains of our closest relatives, the apes. Comparative analyses of the spatial organization of cortical neurons, including minicolumns, can aid our understanding of the functionally relevant aspects of microcircuitry. We measured horizontal spacing distance and gray-level ratio in layer III of 4 regions of human and ape cortex in all 6 living hominoid species: frontal pole (Brodmann area [BA] 10), and primary motor (BA 4), primary somatosensory (BA 3), and primary visual cortex (BA 17). Our results identified significant differences between humans and apes in the frontal pole (BA 10). Within the human brain, there were also significant differences between the frontal pole and 2 of the 3 regions studied (BA 3 and BA 17). Differences between BA 10 and BA 4 were present but did not reach significance. These findings in combination with earlier findings on BA 44 and BA 45 suggest that human brain evolution was likely characterized by an increase in the number and width of minicolumns and the space available for interconnectivity between neurons in the frontal lobe, especially the prefrontal cortex.

DOI: 10.1093/cercor/bhq191
Alternate Journal: Cereb. Cortex
Related MOCA Topics: