Brodmann area 6 (BA6) is part of the
frontal
Front may refer to:
Arts, entertainment, and media Films
* ''The Front'' (1943 film), a 1943 Soviet drama film
* ''The Front'', 1976 film
Music
*The Front (band), an American rock band signed to Columbia Records and active in the 1980s and ea ...
cortex in the
human brain
The human brain is the central organ of the human nervous system, and with the spinal cord makes up the central nervous system. The brain consists of the cerebrum, the brainstem and the cerebellum. It controls most of the activities of the ...
. Situated just anterior to the
primary motor cortex
The primary motor cortex (Brodmann area 4) is a brain region that in humans is located in the dorsal portion of the frontal lobe. It is the primary region of the motor system and works in association with other motor areas including premotor co ...
(
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 6 is also called agranular frontal area 6 in humans because it lacks an internal granular cortical layer (layer IV). It is a subdivision of the
cytoarchitecturally
Cytoarchitecture (Ancient Greek language, Greek ''wiktionary:κύτος#Ancient_Greek, κύτος''= "cell" + ''wiktionary:ἀρχιτέκτων#Ancient_Greek, ἀρχιτεκτονική''= "architecture"), also known as cytoarchitectonics, is th ...
defined precentral region of cerebral cortex. In the human brain, it is located on the portions of the
precentral gyrus that are not occupied by
Brodmann area 4; furthermore, BA6 extends onto the caudal portions of the
superior frontal and
middle frontal gyri. It extends from the
cingulate sulcus on the medial aspect of the hemisphere to the
lateral sulcus
In neuroanatomy, the lateral sulcus (also called Sylvian fissure, after Franciscus Sylvius, or lateral fissure) is one of the most prominent features of the human brain. The lateral sulcus is a deep fissure in each hemisphere that separates the ...
on the lateral aspect. It is bounded rostrally by the granular frontal region and caudally by the gigantopyramidal area 4 (Brodmann, 1909).
In animals
Brodmann area 6 is a cytoarchitecturally defined portion of the frontal lobe of the
guenon. Brodmann-1909 regarded it as topographically and cytoarchitecturally
homologous to the human agranular frontal area 6 and noted that, in the monkey, area 4 is larger than area 6, whereas, in the human, area 6 is larger than area 4. Distinctive features (Brodmann-1905): It is thick relative to other cortical areas; the transition from cortex to subcortical
white matter
White matter refers to areas of the central nervous system (CNS) that are mainly made up of myelinated axons, also called tracts. Long thought to be passive tissue, white matter affects learning and brain functions, modulating the distribution ...
is gradual; cell layers are indistinct; and the internal
granular layer (IV) is absent.
[ ]
Image
File:Brodmann area 6 animation small.gif, Animation.
File:Brodmann area 6 frontal.jpg, front view.
File:Brodmann area 6 lateral.jpg, Lateral view.
File:Brodmann area 6 medial.jpg, Medial view.
See also
*
Brodmann area
*
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
* Med ...
*
Korbinian Brodmann
References
External links
* – agranular frontal area 6
* – Brodmann area 6
{{Prosencephalon
06
Frontal lobe