Brodmann area 19 | |
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![]() Brodmann area 19 is shown in orange | |
Details | |
Identifiers | |
Latin | area peristriata |
NeuroNames | 1028 |
NeuroLex ID | birnlex_1750 |
FMA | 68616 |
Anatomical terms of neuroanatomy |
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 (or peristriate) cortex. In humans with normal sight, extrastriate cortex is a visual association area, with feature-extracting, shape recognition, attentional, and multimodal integrating functions.
This area is also known as peristriate area 19, and it refers to a subdivision of the cytoarchitecturally defined occipital region of cerebral cortex. In the human it is located in parts of the lingual gyrus, the cuneus, the lateral occipital gyrus (H) and the superior occipital gyrus (H) of the occipital lobe where it is bounded approximately by the parieto-occipital sulcus. It is bounded on one side by the parastriate area 18, which it surrounds. It is bounded rostrally by the angular area 39 (H) and the occipitotemporal area 37 (H) (Brodmann-1909).
Brodmann area 19-1909 is a subdivision of the cerebral cortex of the guenon defined on the basis of cytoarchitecture. It is cytoarchitecturally homologous to the peristriate area 19 of the human (Brodmann-1909). Distinctive features (Brodmann-1905): Compared to Brodmann area 18-1909, the pyramidal cells of sublayer 3b of the external pyramidal layer (III) are not as densely distributed, the layer is not as narrow, and its boundary with the internal granular layer (IV) is not as distinct; the cells in sublayer 3b are concentrated at its outer boundary leaving a narrow clear zone with no large pyramidal cells adjacent to layer IV; the granule cells of layer IV are less densely distributed and are intermixed with larger polymorphic cells so that, while the layer is still quite dark and prominent, it is somewhat widened and not as self-contained; the internal pyramidal layer (V) is characterized by large pyramidal ganglion cells, most in small groups, a pattern not seen in area 18; the cells in the multiform layer (VI) are clearly larger than in area 18; overall, area 19 is somewhat thicker and less densely populated than area 18.
Area 19 is a histologically delineated band anterolaterally abutting visual area 18. Single-cell electrophysiological recordings from area 19 in the cat suggest sensitivity to motion-delineated forms; recordings from primates have yielded varying results, indicating that this area may be a heterogeneous collection of visual areas, with multiple incomplete representations of the visual scene.
In humans, this band is reputed to contain regions of the visual areas designated V3, V4, V5 (also known as the middle temporal area, or MT), and V6 (also known as dorsomedial area) in the primate. Functional magnetic resonance imaging shows the existence of various retinotopic maps within area 19. In general, the diverse fields that comprise area 19 have reciprocal connections with areas 17 and 18, as well as posterior parietal and inferior temporal association areas.
Area 19 has been noted to receive inputs from the retina via the superior colliculus and pulvinar and may contribute to the phenomenon of blindsight. In patients blind from a young age, the area has been found to be activated by somatosensory stimuli.
Because of these findings, it is thought that area 19 is the differentiation point of the two visual streams of the 'what' and 'where' visual pathways. The dorsal region may contain motion-sensitive neurons, and ventral areas may be specialised for object recognition.
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. The cerebral cortex mostly consists of the six-layered neocortex, with just 10% consisting of the allocortex. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemispheres. The two hemispheres are joined beneath the cortex by the corpus callosum. The cerebral cortex is the largest site of neural integration in the central nervous system. It plays a key role in attention, perception, awareness, thought, memory, language, and consciousness. The cerebral cortex is part of the brain responsible for cognition.
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.
Brodmann area 23 (BA23) is a region in the brain that lies inside the posterior cingulate cortex. It lies between Brodmann area 30 and Brodmann area 31 and is located on the medial wall of the cingulate gyrus between the callosal sulcus and the cingulate sulcus.
Brodmann area 6 (BA6) is 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 (SMA). This large area of the frontal cortex is believed to play a role in planning complex, coordinated movements.
Brodmann area 8 is one of Brodmann's cytologically defined regions of the brain. It is involved in planning complex movements.
Brodmann area 9, or BA9, refers to a cytoarchitecturally defined portion of the frontal cortex in the brain of humans and other primates. It contributes to the dorsolateral and medial prefrontal cortex.
Brodmann area 10 is the anterior-most portion of the prefrontal cortex in the human brain. BA10 was originally defined broadly in terms of its cytoarchitectonic traits as they were observed in the brains of cadavers, but because modern functional imaging cannot precisely identify these boundaries, the terms anterior prefrontal cortex, rostral prefrontal cortex and frontopolar prefrontal cortex are used to refer to the area in the most anterior part of the frontal cortex that approximately covers BA10—simply to emphasize the fact that BA10 does not include all parts of the prefrontal cortex.
Brodmann area 5 is one of Brodmann's cytoarchitectural defined regions of the brain. It is involved in somatosensory processing, movement and association, and is part of the posterior parietal cortex.
Brodmann area 7 is one of Brodmann's cytologically defined regions of the brain corresponding to precuneus and superior parietal lobule (SPL). It is involved in locating objects in space. It serves as a point of convergence between vision and proprioception to determine where objects are in relation to parts of the body.
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, or BA21, is part of the temporal cortex in the human brain. The region encompasses most of the lateral temporal cortex and is also known as middle temporal area 21. In the human it corresponds approximately to the middle temporal gyrus.
Brodmann area 37, or BA37, is part of the temporal cortex in the human brain. It contains the fusiform gyrus which in turn contains the fusiform face area, an area important for the recognition of faces.
Brodmann area 11 is one of Brodmann's cytologically defined regions of the brain. It is in the orbitofrontal cortex which is above the eye sockets (orbitae). It is involved in decision making, processing rewards, and encoding new information into long-term memory.
Brodmann area 4 refers to the primary motor cortex of the human brain. It is located in the posterior portion of the frontal lobe.
Brodmann area 24 is part of the anterior cingulate in the human brain.
The Brodmann area 32, also known in the human brain as the dorsal anterior cingulate area 32, refers to a subdivision of the cytoarchitecturally defined cingulate cortex. In the human it forms an outer arc around the anterior cingulate gyrus. The cingulate sulcus defines approximately its inner boundary and the superior rostral sulcus (H) its ventral boundary; rostrally it extends almost to the margin of the frontal lobe. Cytoarchitecturally it is bounded internally by the ventral anterior cingulate area 24, externally by medial margins of the agranular frontal area 6, intermediate frontal area 8, granular frontal area 9, frontopolar area 10, and prefrontal area 11-1909. (Brodmann19-09).
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 26 is the name for a small part of the brain.
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 is part of the entorhinal cortex (Brodmann-1909).