Biomaterial Database

Reconstructing the areal organization of the neocortex of the first mammals. 2011

Jon H Kaas

Department of Psychology, Vanderbilt University, Nashville, TN 37240-7817, USA. jon.h.kaas@vanderbilt.edu

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.

UI	MeSH Term	Description	Entries
D008322	Mammals	Warm-blooded vertebrate animals belonging to the class Mammalia, including all that possess hair and suckle their young.	Mammalia,Mammal
D005075	Biological Evolution	The process of cumulative change over successive generations through which organisms acquire their distinguishing morphological and physiological characteristics.	Evolution, Biological
D005580	Fossils	Remains, impressions, or traces of animals or plants of past geological times which have been preserved in the earth's crust.	Fossil
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D019579	Neocortex	The largest portion of the CEREBRAL CORTEX in which the NEURONS are arranged in six layers in the mammalian brain: molecular, external granular, external pyramidal, internal granular, internal pyramidal and multiform layers.	Cerebral Neocortex,External Granular Layer,Isocortex,Neocortical External Granular Layer,Neocortical External Pyramidal Layer,Neocortical Internal Granular Layer,Neocortical Internal Pyramidal Layer,Neocortical Molecular Layer,Neocortical Multiform Layer,Neopallial Cortex,Neopallium,Substantia Corticalis,Cerebral Neocortices,Cortex, Neopallial,Corticali, Substantia,Corticalis, Substantia,Cortices, Neopallial,External Granular Layers,Granular Layer, External,Granular Layers, External,Isocortices,Layer, External Granular,Layer, Neocortical Molecular,Layer, Neocortical Multiform,Layers, External Granular,Layers, Neocortical Molecular,Layers, Neocortical Multiform,Molecular Layer, Neocortical,Molecular Layers, Neocortical,Multiform Layer, Neocortical,Multiform Layers, Neocortical,Neocortex, Cerebral,Neocortical Molecular Layers,Neocortical Multiform Layers,Neocortices,Neocortices, Cerebral,Neopallial Cortices,Neopalliums,Substantia Corticali