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A cortical minicolumn is a vertical column through the 
Many sources support the existence of minicolumns, especially Mountcastle, with strong evidence reviewed by Buxhoeveden and Casanova who conclude "... the minicolumn must be considered a strong model for cortical organization" and "
The human connectome: A structural description of the human brain
PLoS Comput. Biol. 2005 Sep1(4):e42. Jones describes a variety of observations that may be interpreted as mini- or micro-columns and gives example numbers from 11 to 142 neurons per minicolumn.
Lippincott’s Illustrated Reviews: Neuroscience
accessed Nov 10 2013. Chapter 13, II.A, "Histological organization of the cortex" (perhaps 90%) of cortical neurons are neocortical neurons. Johansson and Lansner use an estimate of 2×1010 neurons in the neocortex and an estimate of 100 neurons per minicolumn, yielding an estimate of 2×108 minicolumns. Sporns et al. give an estimate of 2×107 – 2×108 minicolumns.Sporns O, Tononi G, Kötter R
The human connectome: A structural description of the human brain
PLoS Comput. Biol. 2005 Sep1(4):e42
cortical layers
The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of a ...
of the brain. Neurons within the microcolumn "receive common inputs, have common outputs, are interconnected, and may well constitute a fundamental computational unit of the cerebral cortex". Minicolumns comprise perhaps 80–120 neurons, except in the primate primary visual cortex (V1), where there are typically more than twice the number. There are about 2×108 minicolumns in humans. From calculations, the diameter of a minicolumn is about 28–40 μm. Minicolumns grow from progenitor cells within the embryo and contain neurons within multiple layers (2–6) of the cortex.
Many sources support the existence of minicolumns, especially Mountcastle, with strong evidence reviewed by Buxhoeveden and Casanova who conclude "... the minicolumn must be considered a strong model for cortical organization" and "he minicolumn is
He or HE may refer to:
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/nowiki> the most basic and consistent template by which the neocortex
The neocortex, also called the neopallium, isocortex, or the six-layered cortex, is a set of layers of the mammalian cerebral cortex involved in higher-order brain functions such as sensory perception, cognition, generation of motor commands, sp ...
organizes its neurones, pathways, and intrinsic circuits".
Cortical minicolumns can also be called cortical microcolumns. Cells in 50 μm minicolumn all have the same receptive field; adjacent minicolumns may have different fields.
Number of neurons
Estimates of number of neurons in a minicolumn range from 80–100 neurons.Sporns O, Tononi G, Kötter RThe human connectome: A structural description of the human brain
PLoS Comput. Biol. 2005 Sep1(4):e42. Jones describes a variety of observations that may be interpreted as mini- or micro-columns and gives example numbers from 11 to 142 neurons per minicolumn.
Number of minicolumns
Estimates of the number of neurons in cortex or in neocortex are on the order of 2×1010. MostClaudia Krebs MD PhD, Joanne Weinberg PhD, Elizabeth Akesson MScLippincott’s Illustrated Reviews: Neuroscience
accessed Nov 10 2013. Chapter 13, II.A, "Histological organization of the cortex" (perhaps 90%) of cortical neurons are neocortical neurons. Johansson and Lansner use an estimate of 2×1010 neurons in the neocortex and an estimate of 100 neurons per minicolumn, yielding an estimate of 2×108 minicolumns. Sporns et al. give an estimate of 2×107 – 2×108 minicolumns.Sporns O, Tononi G, Kötter R
The human connectome: A structural description of the human brain
PLoS Comput. Biol. 2005 Sep1(4):e42
Size of minicolumns
The minicolumn measures of the order of 40–50 μm in transverse diameter; 35–60 μm; 50 μm with 80 μm spacing, or 30 μm with 50 μm. Larger sizes may not be of human minicolumns, for example macaque monkey V1 minicolumns are 31 μm diameter, with 142 pyramidal cells — 1270 columns per mm2. Similarly, the cat V1 has much bigger minicolumns, ~56 μm. The size can also be calculated from area considerations. If cortex (both hemispheres) is 1.27×1011 μm2 then if there are 2×108 minicolumns in the neocortex then each is 635 μm2, giving a diameter of 28 μm (if the cortex area were doubled to the commonly quoted value, this would rise to 40 μm). Johansson and Lansner do a similar calculation and arrive at 36 μm (p51, last para). Downwards projecting axons in minicolumns are ≈10 μm in diameter, periodicity and density similar to those within the cortex, but not necessarily coincident.See also
*Cortical column
A cortical column is a group of neurons forming a cylindrical structure through the cerebral cortex of the brain perpendicular to the cortical surface. The structure was first identified by Mountcastle in 1957. He later identified cortical minicolu ...
References
External links
* {{DEFAULTSORT:Cortical Minicolumn Cerebrum