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Corpus callosum

January 01, 1970

For the film, see *Corpus Callosum.

The corpus callosum (Latin for "tough body"), also callosal commissure, is a wide, thick nerve tract, consisting of a flat bundle of commissural fibers, beneath the cerebral cortex in the brain. The corpus callosum is only found in placental mammals.[1] It spans part of the longitudinal fissure, connecting the left and right cerebral hemispheres, enabling communication between them. It is the largest white matter structure in the human brain, about 10 in (250 mm) in length and consisting of 200–300 million axonal projections.[2][3]

Corpus callosum
Corpus callosum from above, front part at the top of the image.
Sagittal section of brain, front part to the left. The corpus callosum can be seen in the center, in light gray
Details
Pronunciation/ˈkɔːrpəs kəˈloʊsəm/
Part ofHuman brain
PartsGenu, rostrum, trunk, splenium
Identifiers
MeSHD003337
NeuroNames191
NeuroLex IDbirnlex_1087
TA98A14.1.09.241
TA25604
FMA86464
Anatomical terms of neuroanatomy
[edit on Wikidata]

A number of separate nerve tracts, classed as subregions of the corpus callosum, connect different parts of the hemispheres. The main ones are known as the genu, the rostrum, the trunk or body, and the splenium.[4]

Structure edit

 
MRI of corpus callosum and its named parts
 
Corpus callosum

The corpus callosum forms the floor of the longitudinal fissure that separates the two cerebral hemispheres. Part of the corpus callosum forms the roof of the lateral ventricles.[5]

The corpus callosum has four main parts – individual nerve tracts that connect different parts of the hemispheres. These are the rostrum, the genu, the trunk or body, and the splenium.[4] Fibres from the trunk and the splenium known together as the tapetum form the roof of each lateral ventricle.[6]

The front part of the corpus callosum, towards the frontal lobes, is called the genu ("knee"). The genu curves downward and backward in front of the septum pellucidum, diminishing greatly in thickness. The lower, much thinner part is the rostrum and is connected below with the lamina terminalis, which stretches from the interventricular foramina to the recess at the base of the optic stalk. The rostrum is named for its resemblance to a bird's beak.

The end part of the corpus callosum, towards the cerebellum, is called the splenium. This is the thickest part, and overlaps the tela choroidea of the third ventricle and the midbrain, and ends in a thick, convex, free border. Splenium translates as "bandage" in Greek.

The trunk of the corpus callosum lies between the splenium and the genu.

The callosal sulcus is a sulcus that separates the corpus callosum from the cingulate gyrus.

Relations edit

On either side of the corpus callosum, the fibers radiate in the white matter and pass to the various parts of the cerebral cortex; those curving forward from the genu into the frontal lobes constitute the forceps minor (also forceps anterior) and those curving backward from the splenium into the occipital lobes, the forceps major (also forceps posterior).[4] Between these two parts is the main body of the fibers, which constitute the tapetum and extend laterally on either side into the temporal lobe, and cover in the central part of the lateral ventricle. The tapetum and anterior commissure share the function of connecting left and right temporal lobes.

The anterior cerebral arteries are in contact with the undersurface of the rostrum; they arch over the front of the genu and are carried along the trunk, supplying the front four-fifths of the corpus callosum.[7]

Neuronal fibers edit

 

The size, amount of myelination, and density of the fibers in the subregions relate to the functions of the brain regions they connect.[8] Myelination is the process of coating neurons with myelin, which helps the transfer of information between neurons. The process is believed to occur until an individual's thirties with peak growth in the first decade of one's life.[9] Thinner, lightly myelinated fibers are slower conducting and they connect the association and prefrontal areas. Thicker and fast-conducting fibers connect the visual and motor areas.[10]

The tractogram pictured shows the nerve tracts from six segments of the corpus callosum, providing linking of the cortical regions between the cerebral hemispheres. Those of the genu are shown in coral; of the premotor, green; of the sensory-motor, purple; of the parietal, pink; of the temporal, yellow; and of the splenium, blue.[11]

Thinner axons in the genu connect the prefrontal cortex between the two halves of the brain; these fibers arise from a fork-like bundle of fibers from the tapetum, the forceps minor. Thicker axons in the trunk of the corpus callosum, interconnect areas of the motor cortex, with proportionately more of the corpus callosum dedicated to supplementary motor regions including Broca's area. The splenium, communicates somatosensory information between the two halves of the parietal lobe and the visual cortex at the occipital lobe, these are the fibers of the forceps major.[12][13]

A study of five- to eighteen-year-olds found a positive correlation between age and callosal thickness.[3]

Variation between sexes edit

The corpus callosum and its relation to sex has been a subject of debate in the scientific and lay communities for over a century. Initial research in the early 20th century claimed the corpus to be different in size between men and women. That research was, in turn, questioned, and ultimately gave way to more advanced imaging techniques that appeared to refute earlier correlations. However, advanced analytical techniques of computational neuroanatomy developed in the 1990s showed that sex differences were clear, but confined to certain parts of the corpus callosum, and that they correlated with cognitive performance in certain tests.[14] An MRI study found that the midsagittal corpus callosum cross-sectional area is, after controlling for brain size, on average, proportionately larger in females.[15]

Using diffusion tensor sequences on MRI machines, the rate at which molecules diffuse in and out of a specific area of tissue, anisotropy can be measured and used as an indirect measurement of anatomical connection strength. These sequences have found consistent sex differences in human corpus callosal shape and microstructure.[which?][16][17][18]

Analysis by shape and size has also been used to study specific three-dimensional mathematical relationships with MRIs, and have found consistent and statistically significant differences between sexes.[19][20] Specific algorithms have found significant differences between the two sexes in over 70% of cases in one review.[21]

A 2005 study on the sizes and structures of the corpus callosum in transgender people found it to be structurally more in line with their declared gender than their assigned sex. [21]

Correlates of size with handedness edit

One study reported that the front portion of the human corpus callosum was 0.75 cm2 or 11% larger in left-handed and ambidextrous people than right-handed people.[22][23] This difference was evident in the anterior and posterior regions of the corpus callosum, but not in the splenium.[22] However, a 2022 meta-analysis failed to confirm any substantial differences in the corpus callosum related to left vs. right- vs. mix-handedness.[24] Others have instead suggested that the degree of handedness negatively correlates with the size of the corpus callosum, meaning that individuals who are capable of using both hands with dexterity would have the largest corpus callosum and vice versa for either left or right hand.[25]

Clinical significance edit

Epilepsy edit

 
Electroencephalography is used to find the source of electrical activity causing a seizure as part of the surgical evaluation for a corpus callosotomy.

The symptoms of refractory (difficult to treat) epilepsy can be reduced by cutting through the corpus callosum in an operation known as a corpus callosotomy lobotomy paralysis.[26] This is usually reserved for cases in which complex or grand mal seizures are produced by an epileptogenic focus on one side of the brain, causing an interhemispheric electrical storm. The diagnostic work up for this procedure involves an electroencephalogram, MRI, PET scan, and evaluation by a neurologist, neurosurgeon, psychiatrist, and neuroradiologist before a partial lobotomy surgery can be considered.[27]

Failure to develop edit

Main article: Agenesis of the corpus callosum

The formation of the corpus callosum begins with the first midline crossing of pioneer axons around week 12 in the prenatal development of the human,[28] or day 15 in the embryogenesis of the mouse.[29] Agenesis of the corpus callosum (ACC) is a rare congenital disorder that is one of the most common brain malformations observed in human beings,[30] in which the corpus callosum is partially or completely absent. ACC is usually diagnosed within the first two years of life, and may manifest as a severe syndrome in infancy or childhood, as a milder condition in young adults, or as an asymptomatic incidental finding. Initial symptoms of ACC usually include seizures, which may be followed by feeding problems and delays in holding the head erect, sitting, standing, and walking. Other possible symptoms may include impairments in mental and physical development, hand-eye coordination, and visual and auditory memory. Hydrocephaly may also occur. In mild cases, symptoms such as seizures, repetitive speech, or headaches may not appear for years. Some syndromes often associated with ACC include Aicardi syndrome, Andermann syndrome, Shapiro syndrome, and acrocallosal syndrome.

ACC is usually not fatal. Treatment usually involves management of symptoms, such as hydrocephaly and seizures, if they occur. Although many children with the disorder lead normal lives and have average intelligence, careful neuropsychological testing reveals subtle differences in higher cortical function compared to individuals of the same age and education without ACC. Children with ACC accompanied by developmental delay and/or seizure disorders should be screened for metabolic disorders.[31]

In addition to agenesis of the corpus callosum, similar conditions are hypogenesis (partial formation), dysgenesis (malformation), and hypoplasia (underdevelopment, including too thin).

Other studies have also linked possible correlations between corpus callosum malformation and autism spectrum disorders.[32][33]

Kim Peek, a savant and the inspiration behind the movie Rain Man, was found with agenesis of the corpus callosum, as part of FG syndrome.

Other disease edit

Anterior corpus callosum lesions may result in akinetic mutism or anomic aphasia. See also:

History edit

The first study of the corpus with relation to gender was by R. B. Bean, a Philadelphia anatomist, who suggested in 1906 that "exceptional size of the corpus callosum may mean exceptional intellectual activity" and that there were measurable differences between men and women. Perhaps reflecting the political climate of the times, he went on to claim differences in the size of the callosum across different races. His research was ultimately refuted by Franklin Mall, the director of his own laboratory.[34]

Of more mainstream impact was a 1982 Science article by Holloway and Utamsing that suggested sex difference in human brain morphology, which related to differences in cognitive ability.[35] Time published an article in 1992 that suggested that, because the corpus is "often wider in the brains of women than in those of men, it may allow for greater cross-talk between the hemispheres—possibly the basis for women’s intuition."[36]

Later publications in the psychology literature have raised doubt as to whether the anatomic size of the corpus is actually different. A meta-analysis of 49 studies since 1980 found that, contrary to de Lacoste-Utamsing and Holloway, no sex difference could be found in the size of the corpus callosum, whether or not any account was taken of larger male brain size.[34] A study in 2006 using thin slice MRI showed no difference in thickness of the corpus when accounting for the size of the subject.[37]

Other animals edit

The corpus callosum is found only in placental mammals, while it is absent in monotremes and marsupials,[38] as well as other vertebrates such as birds, reptiles, amphibians and fish.[39] (Other groups do have other brain structures that allow for communication between the two hemispheres, such as the anterior commissure, which serves as the primary mode of interhemispheric communication in marsupials,[40][41] and which carries all the commissural fibers arising from the neocortex (also known as the neopallium), whereas in placental mammals, the anterior commissure carries only some of these fibers.[42]) In primates, the speed of nerve transmission depends on its degree of myelination, or lipid coating. This is reflected by the diameter of the nerve axon. In most primates, axonal diameter increases in proportion to brain size to compensate for the increased distance to travel for neural impulse transmission. This allows the brain to coordinate sensory and motor impulses. However, the scaling of overall brain size and increased myelination have not occurred between chimpanzees and humans. This has resulted in the human corpus callosum's requiring double the time for interhemispheric communication as a macaque's.[12] The fibrous bundle at which the corpus callosum appears, can and does increase to such an extent in humans that it encroaches upon and wedges apart the hippocampal structures.[43]

Additional images edit

  •  
    Corpus callosum
  •  
    Coronal T2 (grey scale inverted) MRI of the brain at the level of the caudate nuclei emphasizing corpus callosum
  • Tractography of corpus callosum
  •  
    Corpus callosum with anatomography
  •  
    Sagittal post mortem section through the midline brain. The corpus callosum is the curved band of lighter tissue at the center of the brain above the hypothalamus. Its lighter texture is due to higher myelin content, resulting in faster neuronal impulse transmission.

References edit

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External links edit

 
Wikimedia Commons has media related to Corpus callosum.

January 01, 1970
corpus, callosum, film, corpus, callosum, corpus, callosum, latin, tough, body, also, callosal, commissure, wide, thick, nerve, tract, consisting, flat, bundle, commissural, fibers, beneath, cerebral, cortex, brain, corpus, callosum, only, found, placental, ma. For the film see Corpus Callosum The corpus callosum Latin for tough body also callosal commissure is a wide thick nerve tract consisting of a flat bundle of commissural fibers beneath the cerebral cortex in the brain The corpus callosum is only found in placental mammals 1 It spans part of the longitudinal fissure connecting the left and right cerebral hemispheres enabling communication between them It is the largest white matter structure in the human brain about 10 in 250 mm in length and consisting of 200 300 million axonal projections 2 3 Corpus callosumCorpus callosum from above front part at the top of the image Sagittal section of brain front part to the left The corpus callosum can be seen in the center in light grayDetailsPronunciation ˈ k ɔːr p e s k e ˈ l oʊ s e m Part ofHuman brainPartsGenu rostrum trunk spleniumIdentifiersMeSHD003337NeuroNames191NeuroLex IDbirnlex 1087TA98A14 1 09 241TA25604FMA86464Anatomical terms of neuroanatomy edit on Wikidata A number of separate nerve tracts classed as subregions of the corpus callosum connect different parts of the hemispheres The main ones are known as the genu the rostrum the trunk or body and the splenium 4 Contents 1 Structure 1 1 Relations 1 2 Neuronal fibers 1 3 Variation between sexes 2 Correlates of size with handedness 3 Clinical significance 3 1 Epilepsy 3 2 Failure to develop 3 3 Other disease 4 History 5 Other animals 6 Additional images 7 References 8 External linksStructure edit nbsp MRI of corpus callosum and its named parts nbsp Corpus callosum The corpus callosum forms the floor of the longitudinal fissure that separates the two cerebral hemispheres Part of the corpus callosum forms the roof of the lateral ventricles 5 The corpus callosum has four main parts individual nerve tracts that connect different parts of the hemispheres These are the rostrum the genu the trunk or body and the splenium 4 Fibres from the trunk and the splenium known together as the tapetum form the roof of each lateral ventricle 6 The front part of the corpus callosum towards the frontal lobes is called the genu knee The genu curves downward and backward in front of the septum pellucidum diminishing greatly in thickness The lower much thinner part is the rostrum and is connected below with the lamina terminalis which stretches from the interventricular foramina to the recess at the base of the optic stalk The rostrum is named for its resemblance to a bird s beak The end part of the corpus callosum towards the cerebellum is called the splenium This is the thickest part and overlaps the tela choroidea of the third ventricle and the midbrain and ends in a thick convex free border Splenium translates as bandage in Greek The trunk of the corpus callosum lies between the splenium and the genu The callosal sulcus is a sulcus that separates the corpus callosum from the cingulate gyrus Relations edit On either side of the corpus callosum the fibers radiate in the white matter and pass to the various parts of the cerebral cortex those curving forward from the genu into the frontal lobes constitute the forceps minor also forceps anterior and those curving backward from the splenium into the occipital lobes the forceps major also forceps posterior 4 Between these two parts is the main body of the fibers which constitute the tapetum and extend laterally on either side into the temporal lobe and cover in the central part of the lateral ventricle The tapetum and anterior commissure share the function of connecting left and right temporal lobes The anterior cerebral arteries are in contact with the undersurface of the rostrum they arch over the front of the genu and are carried along the trunk supplying the front four fifths of the corpus callosum 7 Neuronal fibers edit nbsp The size amount of myelination and density of the fibers in the subregions relate to the functions of the brain regions they connect 8 Myelination is the process of coating neurons with myelin which helps the transfer of information between neurons The process is believed to occur until an individual s thirties with peak growth in the first decade of one s life 9 Thinner lightly myelinated fibers are slower conducting and they connect the association and prefrontal areas Thicker and fast conducting fibers connect the visual and motor areas 10 The tractogram pictured shows the nerve tracts from six segments of the corpus callosum providing linking of the cortical regions between the cerebral hemispheres Those of the genu are shown in coral of the premotor green of the sensory motor purple of the parietal pink of the temporal yellow and of the splenium blue 11 Thinner axons in the genu connect the prefrontal cortex between the two halves of the brain these fibers arise from a fork like bundle of fibers from the tapetum the forceps minor Thicker axons in the trunk of the corpus callosum interconnect areas of the motor cortex with proportionately more of the corpus callosum dedicated to supplementary motor regions including Broca s area The splenium communicates somatosensory information between the two halves of the parietal lobe and the visual cortex at the occipital lobe these are the fibers of the forceps major 12 13 A study of five to eighteen year olds found a positive correlation between age and callosal thickness 3 Variation between sexes edit The corpus callosum and its relation to sex has been a subject of debate in the scientific and lay communities for over a century Initial research in the early 20th century claimed the corpus to be different in size between men and women That research was in turn questioned and ultimately gave way to more advanced imaging techniques that appeared to refute earlier correlations However advanced analytical techniques of computational neuroanatomy developed in the 1990s showed that sex differences were clear but confined to certain parts of the corpus callosum and that they correlated with cognitive performance in certain tests 14 An MRI study found that the midsagittal corpus callosum cross sectional area is after controlling for brain size on average proportionately larger in females 15 Using diffusion tensor sequences on MRI machines the rate at which molecules diffuse in and out of a specific area of tissue anisotropy can be measured and used as an indirect measurement of anatomical connection strength These sequences have found consistent sex differences in human corpus callosal shape and microstructure which 16 17 18 Analysis by shape and size has also been used to study specific three dimensional mathematical relationships with MRIs and have found consistent and statistically significant differences between sexes 19 20 Specific algorithms have found significant differences between the two sexes in over 70 of cases in one review 21 A 2005 study on the sizes and structures of the corpus callosum in transgender people found it to be structurally more in line with their declared gender than their assigned sex 21 Correlates of size with handedness editOne study reported that the front portion of the human corpus callosum was 0 75 cm2 or 11 larger in left handed and ambidextrous people than right handed people 22 23 This difference was evident in the anterior and posterior regions of the corpus callosum but not in the splenium 22 However a 2022 meta analysis failed to confirm any substantial differences in the corpus callosum related to left vs right vs mix handedness 24 Others have instead suggested that the degree of handedness negatively correlates with the size of the corpus callosum meaning that individuals who are capable of using both hands with dexterity would have the largest corpus callosum and vice versa for either left or right hand 25 Clinical significance editEpilepsy edit nbsp Electroencephalography is used to find the source of electrical activity causing a seizure as part of the surgical evaluation for a corpus callosotomy The symptoms of refractory difficult to treat epilepsy can be reduced by cutting through the corpus callosum in an operation known as a corpus callosotomy lobotomy paralysis 26 This is usually reserved for cases in which complex or grand mal seizures are produced by an epileptogenic focus on one side of the brain causing an interhemispheric electrical storm The diagnostic work up for this procedure involves an electroencephalogram MRI PET scan and evaluation by a neurologist neurosurgeon psychiatrist and neuroradiologist before a partial lobotomy surgery can be considered 27 Failure to develop edit Main article Agenesis of the corpus callosum The formation of the corpus callosum begins with the first midline crossing of pioneer axons around week 12 in the prenatal development of the human 28 or day 15 in the embryogenesis of the mouse 29 Agenesis of the corpus callosum ACC is a rare congenital disorder that is one of the most common brain malformations observed in human beings 30 in which the corpus callosum is partially or completely absent ACC is usually diagnosed within the first two years of life and may manifest as a severe syndrome in infancy or childhood as a milder condition in young adults or as an asymptomatic incidental finding Initial symptoms of ACC usually include seizures which may be followed by feeding problems and delays in holding the head erect sitting standing and walking Other possible symptoms may include impairments in mental and physical development hand eye coordination and visual and auditory memory Hydrocephaly may also occur In mild cases symptoms such as seizures repetitive speech or headaches may not appear for years Some syndromes often associated with ACC include Aicardi syndrome Andermann syndrome Shapiro syndrome and acrocallosal syndrome ACC is usually not fatal Treatment usually involves management of symptoms such as hydrocephaly and seizures if they occur Although many children with the disorder lead normal lives and have average intelligence careful neuropsychological testing reveals subtle differences in higher cortical function compared to individuals of the same age and education without ACC Children with ACC accompanied by developmental delay and or seizure disorders should be screened for metabolic disorders 31 In addition to agenesis of the corpus callosum similar conditions are hypogenesis partial formation dysgenesis malformation and hypoplasia underdevelopment including too thin Other studies have also linked possible correlations between corpus callosum malformation and autism spectrum disorders 32 33 Kim Peek a savant and the inspiration behind the movie Rain Man was found with agenesis of the corpus callosum as part of FG syndrome Other disease edit Anterior corpus callosum lesions may result in akinetic mutism or anomic aphasia See also Alien hand syndrome Dyslexia without agraphia seen with damage to splenium of corpus callosum Marchiafava Bignami disease a degenerative disease characterised by loss of myelin and necrosis of the corpus callosum Multiple sclerosis with the Dawson s fingers sign Reversible splenial lesion syndrome a rare encephalopathy of unknown origin with a transient lesion in the splenium mostly associated with infectious diseases Septo optic dysplasia de Morsier syndrome Split brain Susac s syndrome characterised by lesions as small holes in the corpus callosumHistory editThe first study of the corpus with relation to gender was by R B Bean a Philadelphia anatomist who suggested in 1906 that exceptional size of the corpus callosum may mean exceptional intellectual activity and that there were measurable differences between men and women Perhaps reflecting the political climate of the times he went on to claim differences in the size of the callosum across different races His research was ultimately refuted by Franklin Mall the director of his own laboratory 34 Of more mainstream impact was a 1982 Science article by Holloway and Utamsing that suggested sex difference in human brain morphology which related to differences in cognitive ability 35 Time published an article in 1992 that suggested that because the corpus is often wider in the brains of women than in those of men it may allow for greater cross talk between the hemispheres possibly the basis for women s intuition 36 Later publications in the psychology literature have raised doubt as to whether the anatomic size of the corpus is actually different A meta analysis of 49 studies since 1980 found that contrary to de Lacoste Utamsing and Holloway no sex difference could be found in the size of the corpus callosum whether or not any account was taken of larger male brain size 34 A study in 2006 using thin slice MRI showed no difference in thickness of the corpus when accounting for the size of the subject 37 Other animals editThe corpus callosum is found only in placental mammals while it is absent in monotremes and marsupials 38 as well as other vertebrates such as birds reptiles amphibians and fish 39 Other groups do have other brain structures that allow for communication between the two hemispheres such as the anterior commissure which serves as the primary mode of interhemispheric communication in marsupials 40 41 and which carries all the commissural fibers arising from the neocortex also known as the neopallium whereas in placental mammals the anterior commissure carries only some of these fibers 42 In primates the speed of nerve transmission depends on its degree of myelination or lipid coating This is reflected by the diameter of the nerve axon In most primates axonal diameter increases in proportion to brain size to compensate for the increased distance to travel for neural impulse transmission This allows the brain to coordinate sensory and motor impulses However the scaling of overall brain size and increased myelination have not occurred between chimpanzees and humans This has resulted in the human corpus callosum s requiring double the time for interhemispheric communication as a macaque s 12 The fibrous bundle at which the corpus callosum appears can and does increase to such an extent in humans that it encroaches upon and wedges apart the hippocampal structures 43 Additional images edit nbsp Corpus callosum nbsp Coronal T2 grey scale inverted MRI of the brain at the level of the caudate nuclei emphasizing corpus callosum source source source source source source Tractography of corpus callosum nbsp Corpus callosum with anatomography nbsp Sagittal post mortem section through the midline brain The corpus callosum is the curved band of lighter tissue at the center of the brain above the hypothalamus Its lighter texture is due to higher myelin content resulting in faster neuronal impulse transmission References edit Velut S Destrieux C Kakou M May 1998 Morphologic anatomy of the corpus callosum Neuro Chirurgie 44 1 Suppl 17 30 PMID 9757322 Corpus callosum Queensland Brain Institute 10 November 2017 a b Luders Eileen Thompson Paul M Toga Arthur W 18 August 2010 The Development of the Corpus Callosum in the Healthy Human Brain Journal of Neuroscience 30 33 10985 10990 doi 10 1523 JNEUROSCI 5122 09 2010 PMC 3197828 PMID 20720105 a b c Gaillard Frank Corpus callosum Radiology Reference Article Radiopaedia org radiopaedia org Carpenter Malcolm 1985 Core text of neuroanatomy 3rd ed Baltimore Williams amp Wilkins pp 26 32 ISBN 978 0683014556 Cumming WJ March 1970 An anatomical review of the corpus callosum Cortex A Journal Devoted to the Study of the Nervous System and Behavior 6 1 1 18 doi 10 1016 s0010 9452 70 80033 8 PMID 4913253 Ropper A Samuels M Klein J 2014 Adams and Victor s Principles of Neurology 10th ed McGraw Hill p 798 ISBN 978 0071794794 Doron KW Gazzaniga MS September 2008 Neuroimaging techniques offer new perspectives on callosal transfer and interhemispheric communication Cortex A Journal Devoted to the Study of the Nervous System and Behavior 44 8 1023 9 doi 10 1016 j cortex 2008 03 007 PMID 18672233 S2CID 5641608 Schlaug Gotfried Jancke Lutz Huang Yanxiong Staiger Jochen F Steinmetz Helmuth April 10 2010 Increased Corpus Callosum Size in Musicians Neuropsychologia 25 4 557 577 doi 10 1177 0743558410366594 PMID 8524453 S2CID 145178347 Aboitiz F 1992 Brain connections interhemispheric fiber systems and anatomical brain asymmetries in humans Biological Research 25 2 51 61 PMID 1365702 NIAAA Publications pubs niaaa nih gov Archived from the original on 2021 11 07 Retrieved 2018 09 17 a b Caminiti Roberto Ghaziri Hassan Galuske Ralf Hof Patrick R Innocenti Giorgio M 2009 Evolution amplified processing with temporally dispersed slow neuronal connectivity in primates Proceedings of the National Academy of Sciences 106 46 19551 6 Bibcode 2009PNAS 10619551C doi 10 1073 pnas 0907655106 JSTOR 25593230 PMC 2770441 PMID 19875694 Hofer Sabine Frahm Jens 2006 Topography of the human corpus callosum revisited Comprehensive fiber tractography using diffusion tensor magnetic resonance imaging NeuroImage 32 3 989 94 doi 10 1016 j neuroimage 2006 05 044 PMID 16854598 S2CID 1164423 Davatzikos C Resnick S M 1998 Sex differences in anatomic measures of interhemispheric connectivity Correlations with cognition in women but not men Cerebral Cortex 8 7 635 40 doi 10 1093 cercor 8 7 635 PMID 9823484 Ardekani B A Figarsky K Sidtis J J 2012 Sexual Dimorphism in the Human Corpus Callosum An MRI Study Using the OASIS Brain Database Cerebral Cortex 23 10 2514 20 doi 10 1093 cercor bhs253 PMC 3767965 PMID 22891036 Dubb Abraham Gur Ruben Avants Brian Gee James 2003 Characterization of sexual dimorphism in the human corpus callosum NeuroImage 20 1 512 9 doi 10 1016 S1053 8119 03 00313 6 PMID 14527611 S2CID 31728989 Westerhausen Rene Kreuder Frank Sequeira Sarah Dos Santos Walter Christof Woerner Wolfgang Wittling Ralf Arne Schweiger Elisabeth Wittling Werner 2004 Effects of handedness and gender on macro and microstructure of the corpus callosum and its subregions A combined high resolution and diffusion tensor MRI study Cognitive Brain Research 21 3 418 26 doi 10 1016 j cogbrainres 2004 07 002 PMID 15511657 Shin Yong Wook Jin Kim Dae Hyon Ha Tae Park Hae Jeong Moon Won Jin Chul Chung Eun Min Lee Jong Young Kim In Kim Sun I et al 2005 Sex differences in the human corpus callosum Diffusion tensor imaging study NeuroReport 16 8 795 8 doi 10 1097 00001756 200505310 00003 PMID 15891572 S2CID 11361577 Kontos Despina Megalooikonomou Vasileios Gee James C 2009 Morphometric analysis of brain images with reduced number of statistical tests A study on the gender related differentiation of the corpus callosum Artificial Intelligence in Medicine 47 1 75 86 doi 10 1016 j artmed 2009 05 007 PMC 2732126 PMID 19559582 Spasojevic Goran Stojanovic Zlatan Suscevic Dusan Malobabic Slobodan 2006 Sexual dimorphism of the human corpus callosum Digital morphometric study Vojnosanitetski Pregled 63 11 933 8 doi 10 2298 VSP0611933S PMID 17144427 a b Yokota Y Kawamura Y Kameya Y 2005 Callosal Shapes at the Midsagittal Plane MRI Differences of Normal Males Normal Females and GID 2005 IEEE Engineering in Medicine and Biology 27th Annual Conference Vol 3 pp 3055 8 doi 10 1109 IEMBS 2005 1617119 ISBN 978 0 7803 8741 6 PMID 17282888 S2CID 351426 a b Witelson S 1985 The brain connection The corpus callosum is larger in left handers Science 229 4714 665 8 Bibcode 1985Sci 229 665W doi 10 1126 science 4023705 PMID 4023705 Driesen Naomi R Raz Naftali 1995 The influence of sex age and handedness on corpus callosum morphology A meta analysis Psychobiology 23 3 240 7 doi 10 3758 BF03332028 S2CID 143304810 Westerhausen Rene Papadatou Pastou Marietta 2022 Handedness and midsagittal corpus callosum morphology a meta analytic evaluation Brain Structure and Function 227 2 545 559 doi 10 1007 s00429 021 02431 4 PMC 8843913 PMID 34851460 Luders Eileen Cherbuin Nicolas Thompson Paul M Gutman Boris Anstey Kaarin J Sachdev Perminder Toga Arthur W 2010 08 01 When more is less Associations between corpus callosum size and handedness lateralization NeuroImage 52 1 43 49 doi 10 1016 j neuroimage 2010 04 016 ISSN 1053 8119 PMC 2903194 PMID 20394828 Clarke Dave F Wheless James W Chacon Monica M Breier Joshua Koenig Mary Kay McManis Mark Castillo Edward Baumgartner James E 2007 Corpus callosotomy A palliative therapeutic technique may help identify resectable epileptogenic foci Seizure 16 6 545 53 doi 10 1016 j seizure 2007 04 004 PMID 17521926 S2CID 18192521 WebMd Corpus Callotomy Web MD July 18 2010 Archived from the original on July 2 2010 Retrieved July 18 2010 Rakic P Yakovlev PI January 1968 Development of the corpus callosum and cavum septi in man The Journal of Comparative Neurology 132 1 45 72 doi 10 1002 cne 901320103 PMID 5293999 S2CID 40226538 Rash BG Richards LJ 28 May 2001 A role for cingulate pioneering axons in the development of the corpus callosum The Journal of Comparative Neurology 434 2 147 57 doi 10 1002 cne 1170 PMID 11331522 S2CID 29992703 Dobyns W B 1996 Absence makes the search grow longer American Journal of Human Genetics 58 1 7 16 PMC 1914936 PMID 8554070 NINDS Agenesis of the Corpus Callosum Information Page NINDS RightDiagnosis com Archived from the original on 2012 03 24 Retrieved Aug 30 2011 Wegiel Jarek Kaczmarski Wojciech Flory Michael Martinez Cerdeno Veronica Wisniewski Thomas Nowicki Krzysztof Kuchna Izabela Wegiel Jerzy 2018 12 19 Deficit of corpus callosum axons reduced axon diameter and decreased area are markers of abnormal development of interhemispheric connections in autistic subjects Acta Neuropathologica Communications 6 1 143 doi 10 1186 s40478 018 0645 7 ISSN 2051 5960 PMC 6299595 PMID 30567587 Autism May Involve A Lack Of Connections And Coordination In Separate Areas Of The Brain Researchers Find Medical News Today Archived from the original on 2011 10 15 a b Bishop Katherine M Wahlsten Douglas 1997 Sex Differences in the Human Corpus Callosum Myth or Reality PDF Neuroscience amp Biobehavioral Reviews 21 5 581 601 doi 10 1016 S0149 7634 96 00049 8 PMID 9353793 S2CID 9909395 Delacoste Utamsing C Holloway R 1982 Sexual dimorphism in the human corpus callosum Science 216 4553 1431 2 Bibcode 1982Sci 216 1431D doi 10 1126 science 7089533 PMID 7089533 C Gorman 20 January 1992 Sizing up the sexes Time pp 36 43 As cited by Bishop and Wahlsten Luders Eileen Narr Katherine L Zaidel Eran Thompson Paul M Toga Arthur W 2006 Gender effects on callosal thickness in scaled and unscaled space NeuroReport 17 11 1103 6 doi 10 1097 01 wnr 0000227987 77304 cc PMID 16837835 S2CID 14466914 Keeler Clyde E 1933 Absence of the Corpus callosum as a Mendelizing Character in the House Mouse Proceedings of the National Academy of Sciences of the United States of America 19 6 609 11 Bibcode 1933PNAS 19 609K doi 10 1073 pnas 19 6 609 JSTOR 86284 PMC 1086100 PMID 16587795 Sarnat Harvey B and Paolo Curatolo 2007 Malformations of the Nervous System Handbook of Clinical Neurology p 68 permanent dead link Ashwell Ken 2010 The Neurobiology of Australian Marsupials Brain Evolution in the Other Mammalian Radiation p 50 Armati Patricia J Chris R Dickman and Ian D Hume 2006 Marsupials p 175 Butler Ann B and William Hodos 2005 Comparative Vertebrate Neuroanatomy Evolution and Adaptation p 361 Morris H amp Schaeffer J P 1953 The Nervous system The Brain or Encephalon Human anatomy a complete systematic treatise 11th ed pp 920 921 964 965 New York Blakiston External links edit nbsp Wikimedia Commons has media related to Corpus callosum Stained brain slice images which include the corpus callosum at the BrainMaps project Comparative Neuroscience at Wikiversity NIF Search Corpus callosum Archived 2016 03 04 at the Wayback Machine via the Neuroscience Information Framework National Organization for Disorders of the Corpus Callosum A 3D model of corpus callosum Retrieved from https en wikipedia org w index php title Corpus callosum amp oldid 1219621651, wikipedia, wiki, book, books, library,

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