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A cortical minicolumn is a vertical column through the cortical layers of the brain, comprising 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.〔Towards cortex sized artificial neural systems, Christopher Johansson and Anders Lansner, ''Neural Networks'', Vol. 20 #1, pp48–61, Elsevier, January 2007〕 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.〔Jeff Hawkins, Sandra Blakeslee "On Intelligence" p. 94〕 Many sources support the existence of minicolumns, especially Mountcastle,〔The columnar organization of the neocortex, Vernon B. Mountcastle, ''Brain'', Vol. 20 #4, pp701–722, Oxford University Press, April 1997〕 with strong evidence reviewed by Buxhoeveden and Casanova〔The minicolumn hypothesis in neuroscience, Daniel P. Buxhoeveden and Manuel F. Casanova, ''Brain'', Vol. 125 #5, pp935–951, Oxford University Press, May 2002.〕 who conclude "... the minicolumn must be considered a strong model for cortical organization" and " Cortical minicolumns can also be called cortical microcolumns.〔http://www.physics.drexel.edu/~ccruz/micros/index.html〕 Cells in 50 µm minicolumn all have the same receptive field; adjacent minicolumns may have very different fields (Jones, 2000). == Number of neurons in a minicolumn == Estimates of number of neurons in a minicolumn range from 80-100 neurons.〔Buxhoeveden, D. P., & Casanova, M. F. (2002). The minicolumn hypothesis in neuroscience. Brain, 125 (5), 935–951〕〔Mountcastle, V. B. (1997). The columnar organization of the neocortex. Brain, 120, 701–722〕〔Sporns O, Tononi G, Kötter R. (The human connectome: A structural description of the human brain ). PLoS Comput Biol. 2005 Sep1(4):e42.〕 Jones〔Edward G. Jones. Microcolumns in the cerebral cortex. PNAS May 9, 2000 vol. 97 no. 10 5019-5021. doi:10.1073/pnas.97.10.5019〕 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. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Cortical minicolumn」の詳細全文を読む スポンサード リンク
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