External granular layer

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External granular layer may refer to:

The external granular layer of the cerebral cortex is commonly known as layer II. It is different from the internal granular layer of the cerebral cortex.

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Brodmann area 6

Brodmann area 6 (BA6) part of the frontal cortex in the human brain. Situated just anterior to the primary motor cortex (BA4), it is composed of the premotor cortex and, medially, the supplementary motor area, or SMA. This large area of the frontal cortex is believed to play a role in the planning of complex, coordinated movements.

Brodmann area 8

Brodmann area 8 is one of Brodmann's cytologically defined regions of the brain. It is involved in planning complex movements.

Brodmann area 5

Brodmann area 5 is one of Brodmann's cytoarchitectural defined regions of the brain. It is involved in somatosensory processing and association.

Brodmann area 19

Brodmann area 19, or BA 19, is part of the occipital lobe cortex in the human brain. Along with area 18, it comprises the extrastriate cortex. In humans with normal sight, extrastriate cortex is a visual association area, with feature-extracting, shape recognition, attentional, and multimodal integrating functions.

Brodmann area 20

Brodmann area 20, or BA20, is part of the temporal cortex in the human brain. The region encompasses most of the ventral temporal cortex, a region believed to play a part in high-level visual processing and recognition memory.

Brodmann area 21

Brodmann area 21, or BA21, is part of the temporal cortex in the human brain. The region encompasses most of the lateral temporal cortex, a region believed to play a part in auditory processing and language. Language function is left lateralized in most individuals. BA21 is superior to BA20 and inferior to BA40 and BA41.

Brodmann area 4

Brodmann area 4 refers to the primary motor cortex of the human brain. It is located in the posterior portion of the frontal lobe.

Granular layer may refer to:

Brodmann area 24

Brodmann area 24 is part of the anterior cingulate in the human brain.

Brodmann area 14

Brodmann Area 14 is one of Brodmann's subdivisions of the cerebral cortex in the brain. It was defined by Brodmann in the guenon monkey . While Brodmann, writing in 1909, argued that no equivalent structure existed in humans, later work demonstrated that area 14 has a clear homologue in the human ventromedial prefrontal cortex.

Brodmann area 12

Brodmann area 12 is a subdivision of the cerebral cortex of the guenon defined on the basis of cytoarchitecture. It occupies the most rostral portion of the frontal lobe. Brodmann-1909 did not regard it as homologous, either topographically or cytoarchitecturally, to rostral area 12 of the human. Distinctive features (Brodmann-1905): a quite distinct internal granular layer (IV) separates slender pyramidal cells of the external pyramidal layer (III) and the internal pyramidal layer (V); the multiform layer (VI) is expanded, contains widely dispersed spindle cells and merges gradually with the underlying cortical white matter; all cells, including the pyramidal cells of the external and internal pyramidal layers are inordinately small; the internal pyramidal layer (V) also contains spindle cells in groups of two to five located close to its border with the internal granular layer (IV).

Brodmann area 13

Brodmann area 13 is a subdivision of the cerebral cortex as defined on the guenon monkey and on the basis of cytoarchitecture. Brodmann area 13 is found in humans as part of the insula. This structure lies between the lateral and medial layers of the brain. Thus it is sometimes misidentified as not being a Brodmann area.

Brodmann Area 15 is one of Brodmann's subdivisions of the cerebral cortex in the brain.

Brodmann area 28

Brodmann area 28 is a subdivision of the cerebral cortex defined on the basis of cytoarchitecture. It is located on the medial aspect of the temporal lobe and part of the entorhinal area (Brodmann-1909).

Brodmann 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).

The internal granular layer of the cortex, also commonly referred to as the granular layer of the cortex, is the layer IV in the subdivision of the mammalian cortex into 6 layers. The adjective internal is used in opposition to the external granular layer of the cortex, the term granular refers to the granule cells found here.

Anatomy of the cerebellum

The anatomy of the cerebellum can be viewed at three levels. At the level of gross anatomy, the cerebellum consists of a tightly folded and crumpled layer of cortex, with white matter underneath, several deep nuclei embedded in the white matter, and a fluid-filled ventricle in the middle. At the intermediate level, the cerebellum and its auxiliary structures can be broken down into several hundred or thousand independently functioning modules or "microzones". At the microscopic level, each module consists of the same small set of neuronal elements, laid out with a highly stereotyped geometry.

Granular insular cortex refers to a portion of the cerebral cortex defined on the basis of internal structure in the human and macaque, the rat, and the mouse. Classified as neocortex, it is in primates distinguished from adjacent allocortex (periallocortex) by the presence of granular layers – external granular layer (II) and internal granular layer (IV) – and by differentiation of the external pyramidal layer (III) into sublayers. In primates it occupies the posterior part of the insula. In rodents it is located on the lateral surface of the cortex rostrally, dorsal to the gustatory area or, more caudally, dorsal to the agranular insula.