View source

From Citizendium, the Citizens' Compendium

You do not have permission to edit pages, for the following reasons:

• The action you have requested is limited to users in one of the groups Users, Sysops, editors.
• You must confirm your e-mail address before editing pages. Please set and validate your e-mail address through your user preferences.

You can view and copy the source of this page:

{{subpages}} {{Image|ComparitiveBrainSize.jpg|right|350px|Comparative anatomy of adult brains from various vertebrate species, highlighting the differences in [[brain size|size]] and gyrification.}} <!-- <imagemap> Image:ComparitiveBrainSize.jpg|thumb|right|350px|Comparative anatomy of adult brains from various vertebrate species, highlighting the differences in brain size and gyrification. default [[Brain evolution]] rect 16 230 205 480 [[Dolphin|Dolphin]] poly 202 378 227 363 230 361 244 374 203 407 204 377 [[Dolphin|Dolphin]] rect 288 408 381 478 [[Macaque|Macaque]] rect 231 390 354 406 [[Macaque|Macaque]] poly 215 227 330 229 404 296 404 393 356 392 346 385 268 380 221 291 [[Gorilla|Gorilla]] rect 0 37 245 225 [[Human|Human]] poly 205 4 208 29 255 37 255 222 341 227 402 260 431 237 537 175 535 44 348 2 [[Elephant|Elephant]] rect 15 3 198 30 [[Human|Human]] rect 205 432 282 484 [[Allometry|Allometry]] rect 381 429 501 473 [[Mouse|Mouse]] rect 405 344 531 429 [[Cat|Cat]] poly 409 261 459 225 536 224 543 341 505 341 494 342 492 345 415 342 [[Dog|Dog]] desc none </imagemap> --> In the brain sciences, '''gyrification''' (or ''gyration''/''sulcation'', ''cortical folding'', ''cortical convolution'', ''fissuration'' or ''fissurization'') refers to both the process and the extent of folding of the [[cerebral cortex]] in [[mammal]]s as a consequence of brain growth during [[embryonic development|embryonic]] and early [[postnatal development]]. In the process (also known as ''gyrogenesis''), [[gyrus|gyri]] (ridges) and [[sulcus|sulci]] (grooves) form on the external surface of the brain (i.e. at the boundary between the [[cerebrospinal fluid]] and the [[gray matter]])<ref name=Armstrong1995>{{cite journal | author = Armstrong, E. | coauthors = Schleicher, A.; Omran, H.; Curtis, M.; Zilles, K. | year = 1995 | title = The Ontogeny of Human Gyrification | journal = Cerebral Cortex | volume = 5 | issue = 1 | pages = 56-63 | url = http://cercor.oxfordjournals.org/cgi/content/abstract/5/1/56 }}</ref>. A low extent of gyrification in a given brain is commonly referred to as [[lissencephaly]] (which may range from [[agyria]], the total absence of folding, to [[pachygyria]]<ref name=Dhellemmes1988>{{citation | last1 = Dhellemmes | first1 = C. | last2 = Girard | first2 = S. | last3 = Dulac | first3 = O. | last4 = Robain | first4 = O. | last5 = Choiset | first5 = A. | last6 = Tapia | first6 = S. | year = 1988 | title = Agyria—pachygyria and Miller-Dieker syndrome: clinical, genetic and chromosome studies | journal = Human Genetics | volume = 79 | issue = 2 | pages = 163–167 | doi = 10.1007/BF00280557 | url = http://www.springerlink.com/index/QQR0H684886267X9.pdf }}</ref>), while [[gyrencephaly]] describes a high degree of folding<ref name=Francis2006>{{citation | last1 = Francis | first1 = F. | last2 = Meyer | first2 = G. | last3 = Fallet-Bianco | first3 = C. | last4 = Moreno | first4 = S. | last5 = Kappeler | first5 = C. | last6 = Socorro | first6 = A.C. | last7 = Tuy | first7 = F.P.D. | last8 = Beldjord | first8 = C. | last9 = Chelly | first9 = J. | year = 2006 | title = Human disorders of cortical development: from past to present | journal = European Journal of Neuroscience | volume = 23 | issue = 4 | pages = 877–893 | doi = 10.1111/j.1460-9568.2006.04649.x }}</ref>. The term ''gyrification'' is also sometimes used instead of the more common term ''[[foliation]]''<ref name=Demaerel2002>{{citation | last = Demaerel | first = P. | year = 2002 | title = Abnormalities of cerebellar foliation and fissuration: classification, neurogenetics and clinicoradiological correlations | journal = Neuroradiology | volume = 44 | issue = 8 | pages = 639–646 | doi = 10.1007/s00234-002-0783-1 | url = http://www.springerlink.com/index/KBKU4WR1MXNU7CU9.pdf }}</ref> to describe the folding patterns of the vertebrate [[cerebellum]]<ref name=Mares1970>{{citation | last1 = Mares | first1 = V. | last2 = Lodin | first2 = Z. | year = 1970 | title = The cellular kinetics of the developing mouse cerebellum. II. The function of the external granular layer in the process of gyrification | journal = Brain Res | volume = 23 | issue = 3 | pages = 343–352 | doi = 10.1016/0006-8993(70)90061-2 | url = http://www.ncbi.nlm.nih.gov/pubmed/5478302 }}</ref> that is highly convoluted in other [[taxa]], e.g. in [[bird]]s<ref name=Iwaniuk2006>{{citation | author = Iwaniuk, A.N.; Hurd, P.L.; Wylie, D.R. | year = 2006 | title = Comparative Morphology of the Avian Cerebellum: I. Degree of Foliation | journal = Brain Behav Evol | volume = 68 | issue = 1 | pages = 45–62 | doi = 10.1159/000093530 | url = http://www.ncbi.nlm.nih.gov/pubmed/16717442 }}</ref>, and of [[mushroom body]] [[calyx|calyces]] in [[insect]] brains<ref name=Farris2005>{{citation | last1 = Farris | first1 = S.M. | last2 = Roberts | first2 = N.S. | year = 2005 | title = Coevolution of generalist feeding ecologies and gyrencephalic mushroom bodies in insects | journal = Proceedings of the National Academy of Sciences | volume = 102 | issue = 48 | pages = 17394–17399 | doi = 10.1073/pnas.0508430102 | url = http://www.pnas.org/cgi/reprint/102/48/17394.pdf }}</ref>.

• Template:!
• Template:2D and 3D measures of gyrification.png/credit
• Template:Article Specific
• Template:Article Specific In
• Template:Article not approved
• Template:Article not approved IN
• Template:Button off2
• Template:Button on2
• Template:Citation
• Template:Citation/core
• Template:Citation/patent
• Template:Cite journal
• Template:Click
• Template:Clickurl
• Template:ComparitiveBrainSize.jpg/credit
• Template:Credit
• Template:Creditline
• Template:Default3
• Template:Editintro
• Template:Editor error catch
• Template:Every page
• Template:Every page below
• Template:Gyrification/Metadata
• Template:H:title
• Template:Harvard reference/authors
• Template:Image
• Template:Link
• Template:Move
• Template:Not Approved Article
• Template:Not Approved Article In
• Template:Optional3
• Template:Plainlink
• Template:Reflist
• Template:Statusmessage
• Template:Subpage list
• Template:Subpage style
• Template:Subpages (protected)
• Template:Tl
• Template:Tln
• Template:To Approve Info
• Template:To Approve Inner
• Template:X0
• CZ:Ref:Casanova 2004 Reduced Brain Size and Gyrification in the Brains of Dyslexic Patients
• CZ:Ref:DOI:10.1016/j.tig.2007.09.003
• CZ:Ref:DOI:10.1073/pnas.95.3.1242
• CZ:Ref:DOI:10.1093/cercor/9.2.151
• CZ:Ref:DOI:10.1111/j.1469-8749.2009.03281.x
• CZ:Ref:DOI:10.1176/appi.ajp.160.9.1606
• CZ:Ref:DOI:10.1177/088307380401900407
• CZ:Ref:Kerjan 2007 Genetic mechanisms underlying abnormal neuronal migration in classical lissencephaly
• CZ:Ref:Magnotta 1999 Quantitative in Vivo Measurement of Gyrification in the Human Brain: Changes Associated with Aging
• CZ:Ref:PMC1166506
• CZ:Ref:Schaer 2009 Congenital heart disease affects local gyrification in 22q11.2 deletion syndrome

Return to Gyrification.