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Information about Corpus Callosum

Brain: Corpus callosum
Corpus callosum from above. (Anterior portion is at the top of the image.)
Median sagittal section of brain (person faces to the left). Corpus callosum visible at center, in light gray.)
subject #189 828
NeuroNameshier-173
MeSH Corpus+Callosum
The corpus callosum is a structure of the mammalian brain in the longitudinal fissure that connects the left and right cerebral hemispheres. It is the largest white matter structure in the brain, consisting of 200-250 million contralateral axonal projections. It is a wide, flat bundle of axons beneath the cortex. Much of the inter-hemispheric communication in the brain is conducted across the corpus callosum.

Monotremes and marsupials do not have a corpus callosum.

Regions

The posterior portion of the corpus callosum is called the splenium; the anterior is called the genu (or "knee"); between the two is the body.

The most anterior part is the rostrum.

Sexual dimorphism

Regarding the the corpus collosum in humans, claims have been disputed about the significance of gender difference relative to the difference in size of the corpus callosum in males versus females, and analogous racial claims. RB Bean, a Philadelphia anatomist, suggested in 1906 that the "exceptional size of the corpus callosum may mean exceptional intellectual activity" and claimed gender differences, which were refuted by Franklin Mall, the director of his own laboratory.[1]

Of much more substantial popular impact was a 1982 Science article claiming to be the first report of a reliable sex difference in human brain morphology, and arguing for relevance to cognitive gender differences.[2] This paper appears to be the source of a large number of lay explanations of perceived male-female difference in behaviour: For example Time magazine was reported to state in 1992 that the corpus callosum 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 woman’s intuition."[3] It has also been used, for example, as the explanation of an increased single-task orientation of male, relative to female, learners; a smaller male corpus is said to make it harder for the left and right sides of the brain to work together and to explain a greater feminine ability to multitask.

The relationship between known gender-specific biology (such as males having, in general, higher testosterone levels than females) and claims about behaviour (such as human males being more competitive) remains a highly-contested one. However, the scientific dispute in the case of the corpus callosum is not about the implications of biological difference, but whether such a difference actually exists. A substantial review paper performed a meta-analysis of 49 studies and found, contrary to de Lacoste-Utamsing and Holloway, that males have a larger corpus callosum, a relationship that is true whether or not account is taken of larger male brain size.[1] Bishop and Wahlstein found that "the widespread belief that women have a larger splenium than men and consequently think differently is untenable." However, more recent studies using new techniques revealed morphological sex differences in human corpus callosum.[5][6] Whether, and to what extent, these morphological differences are associated with behavioural and cognitive differences between males and females remains unclear.

Other correlations

The corpus callosum has been reported to be significantly larger in musicians than non-musicians,[7] and to be slightly larger in left-handed people than right-handed people.[8]

Pathology

External links

Additional images


Mesal aspect of a brain sectioned in the median sagittal plane.

Coronal section of brain immediately in front of pons.

Coronal section of brain through intermediate mass of third ventricle.

Coronal section of lateral and third ventricles.

Central part and anterior and posterior cornua of lateral ventricles exposed from above.

Coronal section through anterior cornua of lateral ventricles.

Coronal section of brain through anterior commissure.

Diagram showing the positions of the three principal subarachnoid cisternæ.


References

1. ^ Bishop, K.M. and D. Wahlsten. "Sex Differences in the Human Corpus Callosum: Myth or Reality?", Neuroscience and Biobehavioral Reviews, Vol. 21, No. 5, pp. 581–601, 1997.
2. ^ de Lacoste-Utamsing, C., Holloway, R. L. "Sexual dimorphism in the human corpus callosum." Science, 216, 1431–1432, 1982.
3. ^ C Gorman (20 January 1992). "Sizing up the sexes". Time: 36-43. 
4. ^
5. ^ Dubb A, Gur R, Avants B, Gee J. "Characterization of sexual dimorphism in the human corpus callosum." Neuroimage. 2003 Sep;20(1):512-9.
6. ^ Shin YW, Kim DJ, Ha TH, Park HJ, Moon WJ, Chung EC, Lee JM, Kim IY, Kim SI, Kwon JS. "Sex differences in the human corpus callosum: diffusion tensor imaging study." Neuroreport. 2005 May 31;16(8):795-8.
7. ^ Levitin, Daniel J. "This is Your Brain on Music", '
8. ^ Driesen, Naomi R.; Naftali Raz (1995). "The influence of sex, age, and handedness on corpus callosum morphology: A meta-analysis". Psychobiology 23 (3): 240–247. 


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White matter fibers
Association fibers (Uncinate fasciculus, Cingulum, Superior longitudinal fasciculus/Arcuate fasciculus, Inferior longitudinal fasciculus, Inferior occipitofrontal fasciculus, Fornix) Commissural fibers (Corpus callosum, Anterior commissure, Posterior commissure, Commissure of fornix) Projection fibers
In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
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NeuroNames is a system of nomenclature for the human and/or macaque brain.

It is maintained by the University of Washington and is a part of a tool called "BrainInfo". BrainInfo helps one identify structures in the brain.
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Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. Created and updated by the United States National Library of Medicine (NLM), it is used by the MEDLINE/PubMed
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Mammalia
Linnaeus, 1758

Subclasses & Infraclasses
  • Subclass †Allotheria*
  • Subclass Prototheria
  • Subclass Theria

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In animals, the brain or encephalon (Greek for "in the skull"), is the control center of the central nervous system, responsible for behavior. The brain is located in the head, protected by the skull and close to the primary sensory apparatus of vision, hearing,
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cerebral hemisphere (hemispherium cerebrale) is defined as one of the two regions of the brain that are delineated by the body's median plane. The brain can thus be described as being divided into left and right cerebral hemispheres.
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White matter is one of the three main solid components of the central nervous system designated by color. The other two are gray matter and substantia nigra.

Structure


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In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
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axon or nerve fiber, is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma.

Anatomy


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cerebral cortex is a structure within the vertebrate brain with distinct structural and functional properties. In non-living, preserved brains, the outermost layers of the cerebrum has a grey color, hence the name "grey matter".
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Monotremata
C.L. Bonaparte, 1837

Families

†Kollikodontidae
Ornithorhynchidae
Tachyglossidae
†Steropodontidae
Monotremes (from the Greek monos 'single' + trema
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Marsupialia
Illiger, 1811

Orders
  • Didelphimorphia
  • Paucituberculata
  • Microbiotheria
  • Dasyuromorphia
  • Peramelemorphia
  • Notoryctemorphia
  • Diprotodontia
  • Sparassodonta (extinct)
  • Yalkaparidontia (extinct)
Marsupials
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In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
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The posterior end of the corpus callosum is the thickest part, and is termed the splenium.

It overlaps the tela chorioidea of the third ventricle and the mid-brain, and ends in a thick, convex, free border.
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In sciences dealing with the anatomy of animals, precise anatomical terms of location are necessary for a variety of reasons. Non-scientists often wonder why zoological and human anatomists use complex terminology to describe locations on a body, when common terms like "up",
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The anterior end of the corpus callosum is named the genu, and is bent downward and backward in front of the septum pellucidum; diminishing rapidly in thickness, it is prolonged backward under the name of the rostrum, which is connected below with the lamina terminalis.
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rostrum, which is connected below with the lamina terminalis.

The anterior cerebral arteries are in contact with the under surface of the rostrum; they then arch over the front of the genu, and are carried backward above the body of the corpus callosum.
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19th century - 20th century - 21st century
1870s  1880s  1890s  - 1900s -  1910s  1920s  1930s
1903 1904 1905 - 1906 - 1907 1908 1909

Year 1906 (MCMVI
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19th century - 20th century - 21st century
1950s  1960s  1970s  - 1980s -  1990s  2000s  2010s
1979 1980 1981 - 1982 - 1983 1984 1985

Year 1982 (MCMLXXXII
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For the peer-reviewed journal, see .
Science '80 was a general science magazine published by the American Association for the Advancement of Science (AAAS).
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The term morphology in biology refers to the outward appearance (shape, structure, color, pattern) of an organism or taxon and its component parts. This is in contrast to physiology, which deals primarily with function.
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time.

One view is that time is part of the fundamental structure of the universe, a dimension in which events occur in sequence, and time itself is something that can be measured.
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19th century - 20th century - 21st century
1960s  1970s  1980s  - 1990s -  2000s  2010s  2020s
1989 1990 1991 - 1992 - 1993 1994 1995

Year 1992 (MCMXCII
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Testosterone is a steroid hormone from the androgen group. Testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid.
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Ralph Holloway (b. 1935) is a notable physical anthropologist at Columbia University and research associate with the American Museum of Natural History. Since obtaining his Ph.
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left-handed primarily uses his or her left hand, more so than the right hand; a left-hander will probably use the left hand for tasks such as personal care, cooking, and so on. Writing is not as precise an indicator of handedness as it might seem.
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Alien hand syndrome (anarchic hand or Dr. Strangelove syndrome) is an unusual neurological disorder, a form of apraxia in which one of the sufferer's hands seems to take on a mind of their own.
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Agenesis of the Corpus Callosum (ACC) is a rare birth defect (congenital disorder) in which there is a complete or partial absence of the corpus callosum. Agenesis of the corpus callosum occurs when the corpus callosum, the band of tissue connecting the two hemispheres of
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Split-brain is a lay term to describe the result when the corpus callosum connecting the two halves of the brain is severed to some degree. The surgical operation to produce this condition is called corpus callosotomy.
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Septo-optic dysplasia (SOD) (de Morsier syndrome)[1][2] is a congenital malformation syndrome manifested by hypoplasia (underdevelopment) of the optic nerve, hypopituitarism, and absence of the septum pellucidum (a midline part of the brain).
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