Brodmann area 22
Encyclopedia
Brodmann area 22 is one of Brodmann
's cytologically defined regions of the brain. It is involved in auditory processing.
(the 22nd numbered Brodmann area
). On the left side of the brain this area helps with generation and understanding of individual words. On the right side of the brain it helps tell the difference between melody
, pitch
, and sound intensity
, that is prosody
. Researchers believe this part of the brain is active in processing language
.
This area is also known as superior temporal area 22, and it refers to a subdivision of the cytoarchitecturally defined temporal region of cerebral cortex
. In the human it corresponds approximately to the lateral and caudal two thirds of the superior temporal gyrus
. It is bounded rostrally by the temporopolar area 38 (H), medially by the posterior transverse temporal area 42 (H), ventrocaudally by the middle temporal area 21 and dorsocaudally by the supramarginal area 40 (H) and the angular area 39 (H) (Brodmann-1909).
The posterior section of Brodmann area 22 is home to Wernicke's area
(most commonly in the left hemisphere only).
defined on the basis of cytoarchitecture. It is cytoarchitecturally homologous to the superior temporal area 22 of the human (Brodmann-1909). Distinctive features (Brodmann-1905): compared to Brodmann area 21
-1909 the cortical thickness of area 22 is greater; cell density is reduced overall and the internal granular layer (IV) is even less developed with fewer cells; there is no detectable boundary between the internal pyramidal layer (V) and the multiform layer (VI); as in area 21, the ganglion cell
s of layer V are numerous and are arrayed adjacent to its boundary with layer IV, but they are plumper and more pyramidal in shape; the polymorphic cells of the multiform layer (VI) become gradually more numerous as one goes deeper and gives way to a wide sublayer 6b of fusiform cells as one approaches the boundary of the cortex with the subcortical white matter
.
Korbinian Brodmann
Korbinian Brodmann was a German neurologist who became famous for his definition of the cerebral cortex into 52 distinct regions from their cytoarchitectonic characteristics.-Life:...
's cytologically defined regions of the brain. It is involved in auditory processing.
Human
Brodmann area 22 is a region of the human brainBrain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...
(the 22nd numbered Brodmann area
Brodmann area
A Brodmann area is a region of the cerebral cortex defined based on its cytoarchitectonics, or structure and organization of cells.-History:...
). On the left side of the brain this area helps with generation and understanding of individual words. On the right side of the brain it helps tell the difference between melody
Melody
A melody , also tune, voice, or line, is a linear succession of musical tones which is perceived as a single entity...
, pitch
Pitch (music)
Pitch is an auditory perceptual property that allows the ordering of sounds on a frequency-related scale.Pitches are compared as "higher" and "lower" in the sense associated with musical melodies,...
, and sound intensity
Intensity (physics)
In physics, intensity is a measure of the energy flux, averaged over the period of the wave. The word "intensity" here is not synonymous with "strength", "amplitude", or "level", as it sometimes is in colloquial speech...
, that is prosody
Prosody (music)
In music, Prosody is the way the composer sets the text of a vocal composition in the assignment of syllables to notes in the melody to which the text is sung. For example, a songwriter might align downbeats or accents with stressed syllables or important words....
. Researchers believe this part of the brain is active in processing language
Language processing
Language processing refers to the way human beings process speech or writing and understand it as language. Most recent theories back the idea that this process is made completely by and inside the brain.- Spoken language :...
.
This area is also known as superior temporal area 22, and it refers to a subdivision of the cytoarchitecturally defined temporal region of cerebral cortex
Cerebral cortex
The cerebral cortex is a sheet of neural tissue that is outermost to the cerebrum of the mammalian brain. It plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness. It is constituted of up to six horizontal layers, each of which has a different...
. In the human it corresponds approximately to the lateral and caudal two thirds of the superior temporal gyrus
Superior temporal gyrus
The superior temporal gyrus is one of three gyri in the temporal lobe of the human brain, which is located laterally to the head, situated somewhat above the external ear.The superior temporal gyrus is bounded by:* the lateral sulcus above;...
. It is bounded rostrally by the temporopolar area 38 (H), medially by the posterior transverse temporal area 42 (H), ventrocaudally by the middle temporal area 21 and dorsocaudally by the supramarginal area 40 (H) and the angular area 39 (H) (Brodmann-1909).
The posterior section of Brodmann area 22 is home to Wernicke's area
Wernicke's area
Wernicke's area is one of the two parts of the cerebral cortex linked since the late nineteenth century to speech . It is involved in the understanding of written and spoken language...
(most commonly in the left hemisphere only).
Guenon
Brodmann area 22 is a subdivision of the cerebral cortex of the guenonGuenon
The guenons are the genus Cercopithecus of Old World monkeys. Not all the members of this genus have the word "guenon" in their common names, and because of changes in scientific classification, some monkeys in other genera may have common names that do include the word "guenon"...
defined on the basis of cytoarchitecture. It is cytoarchitecturally homologous to the superior temporal area 22 of the human (Brodmann-1909). Distinctive features (Brodmann-1905): compared to Brodmann area 21
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...
-1909 the cortical thickness of area 22 is greater; cell density is reduced overall and the internal granular layer (IV) is even less developed with fewer cells; there is no detectable boundary between the internal pyramidal layer (V) and the multiform layer (VI); as in area 21, the ganglion cell
Ganglion cell
A retinal ganglion cell is a type of neuron located near the inner surface of the retina of the eye. It receives visual information from photoreceptors via two intermediate neuron types: bipolar cells and amacrine cells...
s of layer V are numerous and are arrayed adjacent to its boundary with layer IV, but they are plumper and more pyramidal in shape; the polymorphic cells of the multiform layer (VI) become gradually more numerous as one goes deeper and gives way to a wide sublayer 6b of fusiform cells as one approaches the boundary of the cortex with the subcortical white matter
White matter
White matter is one of the two components of the central nervous system and consists mostly of myelinated axons. White matter tissue of the freshly cut brain appears pinkish white to the naked eye because myelin is composed largely of lipid tissue veined with capillaries. Its white color is due to...
.
External links
- For Neuroanatomy of the superior temporal area 22 visit BrainInfo
- For Neuroanatomy of Brodmann area 22 visit BrainInfo
See also
- Brodmann areaBrodmann areaA Brodmann area is a region of the cerebral cortex defined based on its cytoarchitectonics, or structure and organization of cells.-History:...
- List of regions in the human brain