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Brodmann Area 26
Brodmann area 26 is the name for a small part of the brain. Human In the human, this area is called ectosplenial area 26. It is a cytoarchitecturally defined portion of the retrosplenial region of the cerebral cortex. It is a narrow band located in the isthmus of cingulate gyrus adjacent to the fasciolar gyrus internally. It is bounded externally by the granular retrolimbic area 29 (Brodmann-1909). Guenon In the guenon, Brodmann area 26 is a subdivision of the cerebral cortex defined on the basis of cytoarchitecture. The smallest of Brodmann's cortical areas in the monkey, it represents cortex that is less differentiated and smaller in monkey and human than in other species. Brodmann regarded it as topographically and cytoarchitecturally homologous to the combined human ectosplenial area 26, granular retrolimbic area 29 and agranular retrolimbic area 30 (Brodmann-1909). Distinctive features (Brodmann-1905): thin cortex; distinct but narrow layers. See also * Brodmann area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain
The brain is an organ (biology), organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It consists of nervous tissue and is typically located in the head (cephalization), usually near organs for special senses such as visual perception, vision, hearing, and olfaction. Being the most specialized organ, it is responsible for receiving information from the sensory nervous system, processing that information (thought, cognition, and intelligence) and the coordination of motor control (muscle activity and endocrine system). While invertebrate brains arise from paired segmental ganglia (each of which is only responsible for the respective segmentation (biology), body segment) of the ventral nerve cord, vertebrate brains develop axially from the midline dorsal nerve cord as a brain vesicle, vesicular enlargement at the rostral (anatomical term), rostral end of the neural tube, with centralized control over all body segments. All vertebr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytoarchitecture
Cytoarchitecture (from Greek κύτος 'cell' and ἀρχιτεκτονική 'architecture'), also known as cytoarchitectonics, is the study of the cellular composition of the central nervous system's tissues under the microscope. Cytoarchitectonics is one of the ways to parse the brain, by obtaining sections of the brain using a microtome and staining them with chemical agents which reveal where different neurons are located. The study of the parcellation of ''nerve fibers'' (primarily axons) into layers forms the subject of myeloarchitectonics (from Greek μυελός 'marrow' and ἀρχιτεκτονική 'architecture'), an approach complementary to cytoarchitectonics. History of the cerebral cytoarchitecture Defining cerebral cytoarchitecture began with the advent of histology—the science of slicing and staining brain slices for examination. It is credited to the Viennese psychiatrist Theodor Meynert (1833–1892), who in 1867 noticed regional variations in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retrosplenial Region
The retrosplenial cortex (RSC) is a cortical area in the brain comprising Brodmann areas 29 and 30. It is secondary association cortex, making connections with numerous other brain regions. The region's name refers to its anatomical location immediately behind the splenium of the corpus callosum in primates, although in rodents it is located more towards the brain surface and is relatively larger. Its function is currently not well understood, but its location close to visual areas and also to the hippocampal spatial/memory system suggest it may have a role in mediating between perceptual and memory functions, particularly in the spatial domain. However, its exact contribution to either space or memory processing has been hard to pin down. Anatomy There is large variation in the region's size across different species. In humans it comprises roughly 0.3% of the entire cortical surface whereas in rabbits it is at least 10% and in rats it extends for more than half the cerebrum d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebral Cortex
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. It is the largest site of Neuron, neural integration in the central nervous system, and plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The six-layered neocortex makes up approximately 90% of the Cortex (anatomy), cortex, with the allocortex making up the remainder. The cortex is divided into left and right parts by the longitudinal fissure, which separates the two cerebral hemispheres that are joined beneath the cortex by the corpus callosum and other commissural fibers. In most mammals, apart from small mammals that have small brains, the cerebral cortex is folded, providing a greater surface area in the confined volume of the neurocranium, cranium. Apart from minimising brain and cranial volume, gyrification, cortical folding is crucial for the Neural circuit, brain circuitry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isthmus Of Cingulate Gyrus
The cingulate gyrus commences below the rostrum of the corpus callosum, curves around in front of the genu, extends along the upper surface of the body, and finally turns downward behind the splenium, where it is connected by a narrow isthmus with the parahippocampal gyrus The parahippocampal gyrus (or hippocampal gyrus') is a grey matter cortical region, a gyrus of the brain that surrounds the hippocampus and is part of the limbic system. The region plays an important role in memory encoding and retrieval. It ha .... Additional images File:Medial surface of cerebral cortex - gyri.png, Medial surface of cerebral cortex - gyri File:Isthmus_Cingulate_-_DK_ATLAS.png, Isthmus of the cingulate gyrus, medial surface of right hemisphere References External links * http://braininfo.rprc.washington.edu/whereisit.aspx?language=0&requestID=ID163&parentID=ID159&originalID=ID163 * https://web.archive.org/web/20091029114245/http://bstr431.biostr.washington.edu/syl/lab7/lab7.htm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fasciolar Gyrus
The indusium griseum, (supracallosal gyrus, gyrus epicallosus, dorsal hippocampal continuation) consists of a thin membranous layer of grey matter in contact with the upper surface of the corpus callosum and continuous laterally with the grey matter of the cingulate cortex and inferiorly with the hippocampus. It is vestigial in humans and is a remnant of the former position of the hippocampus in lower animals. On either side of the midline of the indusium griseum are two ridges formed by bands of longitudinally directed fibers known as the medial and lateral longitudinal striae. The indusium griseum is prolonged around the splenium of the corpus callosum as a delicate layer, the fasciolar gyrus, (also gyrus fasciolaris) which is continuous below with the surface of the dentate gyrus. The indusium griseum and fasciolar gyrus are very small components of the limbic lobe, and are continuations of the hippocampal formation, forming an unremarkable thin continuous ring of grey matter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Granular Retrolimbic Area 29
Brodmann area 29, also known as granular retrolimbic area 29 or granular retrosplenial cortex, is a cytoarchitecturally defined portion of the retrosplenial region of the cerebral cortex. In the human it is a narrow band located in the isthmus of cingulate gyrus. Cytoarchitecturally it is bounded internally by the ectosplenial area 26 and externally by the agranular retrolimbic area 30 (Brodmann-1909). Brodmann has this to say about area 29, amongst his other comments on it: "An unusual regression of layer II together with layer III is found in the granular retrosplenial cortex, illustrated in Figures 38 to 41 for four different animals. Here, in addition to the regression of layers II and III, there is fusion of the original layers V and VI and at the same time an isolated massive increase of the inner granular layer, that is particularly prominent in Figures 38 and 39;..." See also * Brodmann area * Retrosplenial region The retrosplenial cortex (RSC) is a cortical area i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guenon
The guenons (, ) are Old World monkeys of the genus ''Cercopithecus'' (). Not all members of this genus have the word "guenon" in their common names; also, because of changes in scientific classification, some monkeys in other genera may have common names that include the word "guenon". Nonetheless, the use of the term guenon for monkeys of this genus is widely accepted. All members of the genus are endemic to sub-Saharan Africa, and most are forest monkeys. Many of the species are quite local in their ranges, and some have even more local subspecies. Many are threatened or endangered because of habitat loss. The species currently placed in the genus ''Chlorocebus'', such as vervet monkeys and green monkeys, were formerly considered as a single species in this genus, ''Cercopithecus aethiops''. In the English language, the word "guenon" is apparently of French origin. In French, ''guenon'' was the common name for all species and individuals, both males and females, from the ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity in anatomical structures or genes between organisms of different taxa due to shared ancestry, ''regardless'' of current functional differences. Evolutionary biology explains homologous structures as retained heredity from a common descent, common ancestor after having been subjected to adaptation (biology), adaptive modifications for different purposes as the result of natural selection. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this from Aristotle's biology onwards, and it was explicitly analysed by Pierre Belon in 1555. A common example of homologous structures is the forelimbs of vertebrates, where the bat wing development, wings of bats and origin of avian flight, birds, the arms of primates, the front flipper (anatomy), flippers of whales, and the forelegs of quadrupedalis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agranular Retrolimbic Area 30
Brodmann area 30, also known as agranular retrolimbic area 30, is a subdivision of the cytoarchitecturally defined retrosplenial region of the cerebral cortex. In the human it is located in the isthmus of cingulate gyrus. Cytoarchitecturally it is bounded internally by the granular retrolimbic area 29, dorsally by the ventral posterior cingulate area 23 and ventrolaterally by the ectorhinal area 36 (Brodmann-1909). In primates, Brodmann area 30 demonstrates projections to the mid-dorsolateral prefrontal cortex ( Brodmann areas 46 and 9) and the thalamus. Additionally, approximately 20% of cortical inputs to the entorhinal cortex arise from the retrosplenial cortex. Individuals with lesions to retrosplenial cortex, predominately Brodmann’s area 30, demonstrate dysfunction in their topographical orientation, including defective navigation in novel and familiar environments. See also * Brodmann area * Retrosplenial cortex The retrosplenial cortex (RSC) is a cortical area ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brodmann Area
A Brodmann area is a region of the cerebral cortex, in the human or other primate brain, defined by its cytoarchitecture, or histological structure and organization of cells. The concept was first introduced by the German anatomist Korbinian Brodmann in the early 20th century. Brodmann mapped the human brain based on the varied cellular structure across the cortex and identified 52 distinct regions, which he numbered 1 to 52. These regions, or Brodmann areas, correspond with diverse functions including sensation, motor control, and cognition. History Brodmann areas were originally defined and numbered by the German anatomist Korbinian Brodmann based on the cytoarchitectural organization of neurons he observed in the cerebral cortex using the Nissl method of cell staining. Brodmann published his maps of cortical areas in humans, monkeys, and other species in 1909, along with many other findings and observations regarding the general cell types and laminar organization of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Regions In The Human Brain
The human brain anatomical regions are ordered following standard neuroanatomy hierarchies. Functional, connective, and developmental regions are listed in parentheses where appropriate. Hindbrain (rhombencephalon) Myelencephalon * Medulla oblongata ** Medullary pyramids ** Arcuate nucleus ** Olivary body *** Inferior olivary nucleus ** Rostral ventrolateral medulla ** Caudal ventrolateral medulla ** Solitary nucleus (Nucleus of the solitary tract) **Respiratory center- Respiratory groups *** Dorsal respiratory group *** Ventral respiratory group or Apneustic centre **** Pre-Bötzinger complex **** Botzinger complex **** Retrotrapezoid nucleus **** Nucleus retrofacialis **** Nucleus retroambiguus **** Nucleus para-ambiguus ** Paramedian reticular nucleus ** Gigantocellular reticular nucleus ** Parafacial zone ** Cuneate nucleus ** Gracile nucleus ** Perihypoglossal nuclei *** Intercalated nucleus *** Prepositus nucleus *** Sublingual nucleus ** Area postrema **Medul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
