cerebral cortex

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cortex

 [kor´teks] (pl. cor´tices) (L.)
the outer layer of an organ or other structure, as distinguished from its inner substance or medulla. adj., adj cor´tical.
adrenal cortex (cortex of adrenal gland) the outer, firm layer comprising the larger part of the adrenal gland; it secretes mineralocorticoids, androgens, and glucocorticoids.
cerebellar cortex the superficial gray matter of the cerebellum.
cerebral cortex (cortex cerebra´lis) the convoluted layer of gray matter covering each cerebral hemisphere. See also brain.
renal cortex the granular outer layer of the kidney, composed mainly of glomeruli and convoluted tubules, extending in columns between the pyramids that constitute the renal medulla.
striate cortex part of the occipital lobe that receives the fibers of the optic radiation and serves as the primary receiving area for vision. Called also first visual area.
visual cortex the area of the occipital lobe of the cerebral cortex concerned with vision; the striate cortex is also called the first visual area, and the adjacent second and third visual areas serve as its association areas.

ce·re·bral cor·tex

[TA]
the gray cellular mantle (1-4 mm thick) covering the entire surface of the cerebral hemisphere of mammals; characterized by a laminar organization of cellular and fibrous components such that its nerve cells are stacked in defined layers varying in number from one, as in the archicortex of the hippocampus, to five or six in the larger neocortex; the outermost (molecular or plexiform) layer contains very few cell bodies and is composed largely of the distal ramifications of the long apical dendrites issued perpendicularly to the surface by pyramidal and fusiform cells in deeper layers. From the surface inward, the layers as classified in K. Brodmann's parcellation are: 1) molecular layer [TA]; 2) external granular layer [TA]; 3) external pyramidal layer [TA]; 4) internal granular layer [TA]; 5) internal pyramidal layer [TA]; and 6) multiform layer [TA], many of which are fusiform. This multilaminate organization is typical of the neocortex (homotypic cortex; isocortex [TA] in O. Vogt terminology), which in humans covers the largest part by far of the cerebral hemisphere. The more primordial heterotypic cortex or allocortex (Vogt) has fewer cell layers. A form of cortex intermediate between isocortex and allocortex, called juxtallocortex (Vogt), covers the ventral part of the cingulate gyrus and the entorhinal area of the parahippocampal gyrus.
On the basis of local differences in the arrangement of nerve cells (cytoarchitecture), Brodmann outlined 47 areas in the cerebral cortex that, in functional terms, can be classified into three categories: motor cortex (areas 4 and 6), characterized by a poorly developed internal granular layer (agranular cortex) and prominent pyramidal cell layers; sensory cortex, characterized by a prominent internal granular layer (granular cortex or koniocortex) and comprising the somatic sensory cortex (areas 1-3), the auditory cortex (areas 41 and 42), and the visual cortex (areas 17-19); and association cortex, the vast remaining expanses of the cerebral cortex.
Synonym(s): cortex cerebri [TA], pallium [TA], brain mantle, mantle (2)

cerebral cortex

n.
The extensive outer layer of gray matter of the cerebral hemispheres, largely responsible for higher brain functions, including sensation, voluntary muscle movement, thought, reasoning, and memory.

cerebral cortex

Neurology The outer portion of the brain, the neocortex consisting of gray-colored layers of nerve cells, and the interconnecting neural circuitry, which is intimately linked to cognition. See Limbic system.

ce·re·bral cor·tex

(ser'ĕ-brăl kōr'teks) [TA]
The gray cellular mantle (1-4 mm thick) covering the entire surface of the cerebral hemisphere of mammals; characterized by a laminar organization of cellular and fibrous components such that its nerve cells are stacked in defined layers varying in number from one, as in the archicortex of the hippocampus, to five or six in the larger neocortex; the outermost (molecular or plexiform) layer contains very few cell bodies and is composed largely of the distal ramifications of the long apical dendrites issued perpendicularly to the surface by pyramidal and fusiform cells in deeper layers. From the surface inward, the layers as classified in K. Brodmann's parcellation are: 1) molecular or plexiform layer; 2) outer granular layer; 3) pyramidal cell layer; 4) inner granular layer; 5) inner pyramidal layer (ganglionic layer); and 6) multiform cell layer, many of which are fusiform. This multilaminate organization is typical of theneocortex (homotypic cortex; isocortex in O. Vogt's terminology), which in humans covers the largest part by far of the cerebral hemisphere. The more primordial heterotypic cortex or allocortex (Vogt) has fewer cell layers. A form of cortex intermediate between isocortex and allocortex, called juxtallocortex (Vogt), covers the ventral part of the cingulate gyrus and the entorhinal area of the parahippocampal gyrus. On the basis of local differences in the arrangement of nerve cells (cytoarchitecture), Brodmann outlined 47 areas in the cerebral cortex that, in functional terms, can be classified into three categories: motor cortex (Brodmann areas 4 and 6), characterized by a poorly developed inner granular layer (agranular cortex) and prominent pyramidal cell layers; sensory cortex, characterized by a prominent inner granular layer (granular cortex or koniocortex) and comprising the somatic sensory cortex (Brodmann areas 1-3), the auditory cortex (Brodmann areas 41 and 42), and the visual cortex (Brodmann areas 17-19); and association cortex, the vast remaining expanses of the cerebral cortex.
See also: Brodmann areas

cerebral cortex

The grey outer layer of the cerebral hemispheres, consisting of the layered masses of nerve cell bodies which perform the higher neurological functions.

cerebral cortex

the intricately folded outer layer of the CEREBRUM, being a layer of GREY MATTER forming the most superficial layer of the roof of the CEREBRAL HEMISPHERES in the forebrain of higher vertebrates. The cerebral cortex consists of millions of densely packed nerve cells and is rich in synapses. It is present in reptiles, birds and mammals and in some lower vertebrates. see BRAIN. In man, the cerebral cortex forms about 40% of the brain by weight.

Cerebral cortex

Brain region responsible for reasoning, mood, and perception.

ce·re·bral cor·tex

(ser'ĕ-brăl kōr'teks) [TA]
The gray cellular mantle (1-4 mm thick) covering the entire surface of the cerebral hemisphere of mammals characterized by a laminar organization of cellular and fibrous components. Based on local differences in the arrangement of nerve cells, there are multiple areas that, on the basis of function, can be categorized into three general groups: motor cortex, sensory cortex, and association cortex.