In
neuroanatomy
Neuroanatomy is the study of the structure and organization of the nervous system. In contrast to animals with radial symmetry, whose nervous system consists of a distributed network of cells, animals with bilateral symmetry have segregated, defi ...
, the postcentral gyrus is a prominent
gyrus
In neuroanatomy, a gyrus (pl. gyri) is a ridge on the cerebral cortex. It is generally surrounded by one or more sulci (depressions or furrows; sg. ''sulcus''). Gyri and sulci create the folded appearance of the brain in humans and other ...
in the lateral
parietal lobe
The parietal lobe is one of the four major lobes of the cerebral cortex in the brain of mammals. The parietal lobe is positioned above the temporal lobe and behind the frontal lobe and central sulcus.
The parietal lobe integrates sensory informa ...
of the
human brain
The human brain is the central organ (anatomy), 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 act ...
. It is the location of the
primary somatosensory cortex
In neuroanatomy, the primary somatosensory cortex is located in the postcentral gyrus of the Human brain, brain's parietal lobe, and is part of the somatosensory system. It was initially defined from surface stimulation studies of Wilder Penfield ...
, the main sensory receptive area for the
sense of touch
In physiology, the somatosensory system is the network of neural structures in the brain and body that produce the perception of touch ( haptic perception), as well as temperature ( thermoception), body position (proprioception), and pain. It ...
. Like other sensory areas, there is a map of sensory space in this location, called the ''
sensory homunculus
A cortical homunculus () is a distorted representation of the human body, based on a neurological "map" of the areas and proportions of the human brain dedicated to processing motor functions, or sensory functions, for different parts of the bo ...
''.
The primary somatosensory cortex was initially defined from surface stimulation studies of
Wilder Penfield
Wilder Graves Penfield (January 26, 1891April 5, 1976) was an American-Canadian neurosurgeon. He expanded brain surgery's methods and techniques, including mapping the functions of various regions of the brain such as the cortical homunculus. ...
, and parallel surface potential studies of Bard, Woolsey, and Marshall. Although initially defined to be roughly the same as
Brodmann area
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.
History
Brodmann areas were originally defined and numbered by th ...
s
3,
1 and
2, more recent work by
Kaas has suggested that for homogeny with other sensory fields only area 3 should be referred to as "primary somatosensory cortex", as it receives the bulk of the
thalamocortical projections from the sensory input fields.
Structure
The lateral postcentral gyrus is bounded by:
*
medial longitudinal fissure
The longitudinal fissure (or cerebral fissure, great longitudinal fissure, median longitudinal fissure, interhemispheric fissure) is the deep groove that separates the two cerebral hemispheres of the vertebrate brain. Lying within it is a continu ...
medially (to the middle)
*
central sulcus rostrally (in front)
*
postcentral sulcus
The postcentral sulcus of the parietal lobe lies parallel to, and behind, the central sulcus in the human brain. (A ''sulcus'' is one of the prominent grooves on the surface of the brain.)
The postcentral sulcus divides the postcentral gyrus from ...
caudally
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...
(in back)
*
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 ...
inferiorly
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...
(underneath)
The postcentral gyrus includes
Brodmann area
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.
History
Brodmann areas were originally defined and numbered by th ...
s 1, 2, and 3. Brodmann area 1 occupies the apex of the postcentral gyrus.
See also
*
List of regions in the human brain
Additional images
File:Postcentral gyrus.gif, Postcentral gyrus (animation)
File:Gray726 postcentral gyrus.png, Lateral surface of left cerebral hemisphere, viewed from the side.
File:Blausen 0103 Brain Sensory&Motor.png, Primary cortices, including primary somatosensory cortex (labeled in purple)
File:Postcentral_-_DK_ATLAS.png, Postcentral gyrus, showed on the right hemisphere.
File:Postcentral gyrus coronal sections.gif, Postcentral gyrus highlighted in green on coronal T1 MRI images
File:Postcentral gyrus sagittal sections.gif, Postcentral gyrus highlighted in green on sagittal T1 MRI images
File:Postcentral gyrus transversal sections.gif, Postcentral gyrus highlighted in green on transversal T1 MRI images
External links
* - area 1
* - area 2
* - area 3
{{Authority control
01
Somatosensory system
Gyri
Parietal lobe