title: Systematic, cross-cortex variation in neuron numbers in rodents and primates.
abstract: Uniformity, local variability, and systematic variation in neuron numbers per unit of cortical surface area across species and cortical areas have been claimed to characterize the isocortex. Resolving these claims has been difficult, because species, techniques, and cortical areas vary across studies. We present a stereological assessment of neuron numbers in layers II-IV and V-VI per unit of cortical surface area across the isocortex in rodents (hamster, Mesocricetus auratus; agouti, Dasyprocta azarae; paca, Cuniculus paca) and primates (owl monkey, Aotus trivigratus; tamarin, Saguinus midas; capuchin, Cebus apella); these chosen to vary systematically in cortical size. The contributions of species, cortical areas, and techniques (stereology, "isotropic fractionator") to neuron estimates were assessed. Neurons per unit of cortical surface area increase across the rostro-caudal (RC) axis in primates (varying by a factor of 1.64-2.13 across the rostral and caudal poles) but less in rodents (varying by a factor of 1.15-1.54). Layer II-IV neurons account for most of this variation. When integrated into the context of species variation, and this RC gradient in neuron numbers, conflicts between studies can be accounted for. The RC variation in isocortical neurons in adulthood mirrors the gradients in neurogenesis duration in development.
authors: Behavioral and Evolutionary Neuroscience Group, Department of Psychology and.
authors: Christine J
authors: CJ
authors: Charvet
authors: Center for Applied Mathematics, Cornell University, Ithaca, NY 14853, USA.
authors: Diarmuid J
authors: DJ
authors: Cahalane
authors: Behavioral and Evolutionary Neuroscience Group, Department of Psychology and.
authors: Barbara L
authors: BL
authors: Finlay
mesh_terms: D000818:Animals; D001029:Aotus trivirgatus; D002428:Cebus; D002452:Cell Count; D065469:Cuniculidae; D065468:Dasyproctidae; D008647:Mesocricetus; D019579:Neocortex / Q000166:cytology*; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000166:cytology*; D012452:Saguinus; D013045:Species Specificity
keywords: cortex; development; gradient; numbers
references: J Neurosci. 2013 Apr 24;33(17):7368-83
references: 23616543
references: PLoS One. 2011 Jan 11;6(1):e16113
references: 21264302
references: Proc Natl Acad Sci U S A. 2009 Jun 2;106(22):8963-8
references: 19451636
references: Brain Behav Evol. 2010;76(1):32-44
references: 20926854
references: Front Neuroanat. 2011 Feb 08;5:4
references: 21369349
references: Nature. 1993 Dec 2;366(6454):464-6
references: 8247154
references: Science. 1974 Feb 1;183(4123):425-7
references: 4203022
references: Proc Natl Acad Sci U S A. 2003 Jun 24;100(13):7937-41
references: 12796510
references: Cereb Cortex. 1997 Oct-Nov;7(7):678-89
references: 9373022
references: J Neurosci. 2007 Oct 3;27(40):10777-84
references: 17913911
references: Nat Rev Neurosci. 2009 Oct;10(10):724-35
references: 19763105
references: Brain. 1980 Jun;103(2):221-44
references: 6772266
references: Nature. 1998 Jun 4;393(6684):440-2
references: 9623998
references: Trends Neurosci. 2009 Aug;32(8):443-50
references: 19635637
references: Brain Behav Evol. 2008;72(4):295-306
references: 19088470
references: Science. 2002 Jul 19;297(5580):365-9
references: 12130776
references: Neuroscience. 2001;105(1):7-17
references: 11483296
references: Biol Cybern. 1995 Nov;73(6):529-45
references: 8527499
references: Brain Behav Evol. 2011;77(2):116-30
references: 21525748
references: Anat Rec. 1946 Feb;94:239-47
references: 21015608
references: J Comp Neurol. 2008 Apr 10;507(5):1663-75
references: 18241052
references: J Comp Neurol. 1989 Nov 1;289(1):178-81
references: 2808760
references: Proc Natl Acad Sci U S A. 2010 Sep 7;107(36):15927-32
references: 20798050
references: PLoS Comput Biol. 2006 Jul 21;2(7):e95
references: 16848638
references: J Comp Neurol. 2007 Sep 20;504(3):265-74
references: 17640049
references: Brain Behav Evol. 2011;78(3):248-57
references: 21860220
references: Nature. 2007 Mar 29;446(7135):507-12
references: 17392779
references: Brain Struct Funct. 2013 May;218(3):805-16
references: 22684638
references: J Neurosci. 2005 Mar 9;25(10):2518-21
references: 15758160
references: Neuroscience. 1990;38(1):21-37
references: 2175019
references: Nature. 2001 Feb 1;409(6820):614-8
references: 11214319
references: Anat Rec (Hoboken). 2007 Mar;290(3):330-40
references: 17525948
references: J Comp Neurol. 1988 Dec 15;278(3):344-52
references: 3216047
references: Trends Neurosci. 2001 Jan;24(1):11-7
references: 11163882
references: Evolution. 2012 Aug;66(8):2551-63
references: 22834752
references: J Anat. 1983 Dec;137 ( Pt 4):683-94
references: 6668246
references: Proc Natl Acad Sci U S A. 2013 Jan 22;110(4):1488-93
references: 23297199
references: Proc Natl Acad Sci U S A. 2008 Aug 26;105(34):12099-100
references: 18715998
references: Brain Behav Evol. 2011;78(1):37-50
references: 21691046
references: Curr Protoc Neurosci. 2003 Nov;Chapter 1:Unit 1.11
references: 18428578
references: J Comp Neurol. 2012 Oct 15;520(15):3492-508
references: 22430145
references: Proc Biol Sci. 2005 Jan 7;272(1558):91-100
references: 15875575
references: Brain Behav Evol. 1998;52(4-5):232-42
references: 9787222
references: Brain Behav Evol. 2011;78(4):302-14
references: 21985803
references: Brain Behav Evol. 2007;70(1):57-70
references: 17409735
references: Proc Natl Acad Sci U S A. 2007 Feb 27;104(9):3562-7
references: 17360682
references: Brain Behav Evol. 2007;69(3):176-95
references: 17106195
references: BMC Evol Biol. 2009 Apr 02;9:71
references: 19341461
references: Front Neuroanat. 2012 Jul 18;6:28
references: 22826696
references: Proc Natl Acad Sci U S A. 2012 Jun 26;109 Suppl 1:10640-6
references: 22723357
references: J Comp Neurol. 2001 Jul 2;435(3):263-75
references: 11406810
references: Brain Res. 2005 Aug 2;1052(1):71-81
references: 16018988
references: Science. 1983 Mar 18;219(4590):1349-51
references: 6828866
references: Vis Neurosci. 1996 May-Jun;13(3):585-90
references: 8782386
references: J Comp Neurol. 1982 Sep 20;210(3):278-90
references: 7142443
references: J Neurobiol. 1992 Nov;23(9):1159-71
references: 1469382
references: Front Neural Circuits. 2013 Feb 27;7:30
references: 23450743
references: Folia Primatol (Basel). 1981;35(1):1-29
references: 7014398
references: Exp Neurol. 1990 Jan;107(1):48-62
references: 2295319
references: Proc Natl Acad Sci U S A. 2010 Jul 27;107(30):13485-90
references: 20628011
references: Cereb Cortex. 1993 May-Jun;3(3):171-86
references: 8324368
references: Science. 1995 Jun 16;268(5217):1578-84
references: 7777856
references: Proc Natl Acad Sci U S A. 1963 Feb 15;49:187-93
references: 13959737