Open AccessReconstructing the Areal Organization of the Neocortex of the First Mammals
Author(s) -
Jon Kaas
Publication year - 2011
Publication title -
brain, behavior and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 77
eISSN - 1421-9743
pISSN - 0006-8977
DOI - 10.1159/000327316
Subject(s) - neocortex , biology , neuroscience , cortex (anatomy) , retrosplenial cortex , sensory system , fossil record , paleontology
The fossil record indicates that early mammals had small brains with proportionately little neocortex. Here we consider what is known about the organization of the neocortex in species with the least expanded neocortex from 6 major clades of the mammalian radiation. Common features of the neocortex across these clades include primary and secondary sensory areas, retrosplenial and cingulate cortex, and frontal cortex. Overall, early mammals likely had a core of 15-20 cortical areas that have been retained in most present-day mammals.