All Topics  
Postcentral gyrus

 

 
   Email Print
   Bookmark   Link
 

 

Postcentral gyrus
 
 
  Topics Postcentral gyrus Topic Home

The lateral postcentral gyrus is a prominent structure in the parietal lobe
Parietal lobe

The parietal lobe is a lobe in the brain. It is positioned above the occipital lobe and behind the frontal lobe.The parietal lobe integrates sensory information from different sensory modality, particularly determining spatial sense and navigation....
 of the human brain
Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as cnidarian and echinoderm have a decentralized nervous system without a brain, while sponges lack any nervous system at all....
 and an important landmark. It was initially defined from surface stimulation studies of Penfield, and parallel surface potential studies of Bard, Woolsey, and Marshall. Although initially defined to be roughly the same as Brodmann area
Brodmann area

A Brodmann area is a region of the cerebral cortex defined based on its cytoarchitecture, or organization of cells.Brodmann areas were originally defined and numbered by Korbinian Brodmann based on the organization of neurons he observed in the cortex using the Franz Nissl staining....
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 received the bulk of the thalamocortical projection from the sensory input fields.

lateral postcentral gyrus is bounded by:

It is the location of primary somatosensory cortex, the main sensory receptive area for the sense of touch.






Discussion
Ask a question about 'Postcentral gyrus'
Start a new discussion about 'Postcentral gyrus'
Answer questions from other users
Full Discussion Forum



Encyclopedia


The lateral postcentral gyrus is a prominent structure in the parietal lobe
Parietal lobe

The parietal lobe is a lobe in the brain. It is positioned above the occipital lobe and behind the frontal lobe.The parietal lobe integrates sensory information from different sensory modality, particularly determining spatial sense and navigation....
 of the human brain
Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as cnidarian and echinoderm have a decentralized nervous system without a brain, while sponges lack any nervous system at all....
 and an important landmark. It was initially defined from surface stimulation studies of Penfield, and parallel surface potential studies of Bard, Woolsey, and Marshall. Although initially defined to be roughly the same as Brodmann area
Brodmann area

A Brodmann area is a region of the cerebral cortex defined based on its cytoarchitecture, or organization of cells.Brodmann areas were originally defined and numbered by Korbinian Brodmann based on the organization of neurons he observed in the cortex using the Franz Nissl staining....
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 received the bulk of the thalamocortical projection from the sensory input fields.

Postcentral gyrus

The lateral postcentral gyrus is bounded by:
  • medial longitudinal fissure
    Medial longitudinal fissure

    The great longitudinal fissure is the deep groove which separates the two cerebral hemisphere of the vertebrate brain.The falx cerebri, a dura mater meninges, lies within the medial longitudinal fissure....
     medially
    Anatomical terms of location

    Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
     (to the middle)
  • central sulcus
    Central sulcus

    The central Sulcus is a fold in the cerebral cortex of brains in vertebrates. Also called the central fissure, it was originally called the fissure of Rolando or the Rolandic fissure, after Luigi Rolando....
     rostrally
    Anatomical terms of location

    Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
     (in front)
  • postcentral sulcus
    Postcentral sulcus

    The postcentral sulcus of the parietal lobe lies parallel to, and behind, the central sulcus in the human brain. The postcentral sulcus divides the postcentral gyrus from the remainder of the parietal lobe....
     caudally
    Anatomical terms of location

    Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
     (in back)
  • lateral sulcus
    Lateral sulcus

    The lateral sulcus is one of the most prominent structures of the human brain....
     inferiorly
    Anatomical terms of location

    Standard anatomical terms of location are employed in sciences dealing with the anatomy of animals to avoid ambiguities which might otherwise arise....
     (underneath)


It is the location of primary somatosensory cortex, the main sensory receptive area for the sense of touch. Like other sensory areas, there is a map of sensory space called a homunculus
Homunculus

The concept of a homunculus is, most generally, any representation of a human being. It is often used to illustrate the functioning of a system....
 in this location. For the primary somatosensory cortex, this is called the sensory homunculus. See a somewhat fanciful and highly schematic representation of the sensory homunculus below.

Brodmann areas 3, 1 and 2

Brodmann areas 3, 1 and 2 comprise the primary somatosensory cortex of the human brain
Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as cnidarian and echinoderm have a decentralized nervous system without a brain, while sponges lack any nervous system at all....
. Because Brodmann
Korbinian Brodmann

Korbinian Brodmann was a Germany neurologist who became famous for his definition of the cerebral cortex into 52 distinct regions from their cytoarchitecture characteristics....
 sliced the brain
Brain

The brain is the center of the nervous system in all vertebrate, and most invertebrate, animals. Some primitive animals such as cnidarian and echinoderm have a decentralized nervous system without a brain, while sponges lack any nervous system at all....
 somewhat obliquely, he encountered area 1 first; however, from rostral
Rostral

Rostral can refer to:* Anatomical terms of location#Directions, Top or cephaled, as opposed to caudal or down.* Rostral bone* Rostral column, a monumental scaled column, frequently decorated with ship bows...
 to caudal the Brodmann
Brodmann area

A Brodmann area is a region of the cerebral cortex defined based on its cytoarchitecture, or organization of cells.Brodmann areas were originally defined and numbered by Korbinian Brodmann based on the organization of neurons he observed in the cortex using the Franz Nissl staining....
 designations are 3, 1 and 2, respectively.

This area of cortex, as shown by Wilder Penfield
Wilder Penfield

[Image:Wilder Penfield.jpg|thumb|Dr. Wilder Penfield, 1934]]Wilder Graves Penfield, Order of Merit, Order of Canada, Order of St. Michael and St....
 and others, has the pattern of a homunculus
Homunculus

The concept of a homunculus is, most generally, any representation of a human being. It is often used to illustrate the functioning of a system....
. That is, the legs and trunk fold over the midline; the arms and hands are along the middle of the area shown here; and the face is near the bottom of the figure. While it is not well-shown here, the lips and hands are enlarged on a proper homunculus, since a large number of neuron
Neuron

Neurons are responsive cell in the nervous system that process and transmit information by electrochemical Signal . They are the core components of the brain, the vertebrate spinal cord, the invertebrate ventral nerve cord, and the peripheral nerves....
s in the cerebral cortex
Cerebral cortex

The cerebral cortex is a structure within the brain that plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness....
 are devoted to processing information from these areas.

These areas contain cells that project to the secondary somatosensory cortex.

Clinical significance


Lesions affecting the primary somatosensory cortex produce characteristic symptoms including: agraphesthesia, astereognosia, loss of vibration
Vibration

Vibration refers to mechanical oscillations about an equilibrium point. The oscillations may be periodic function such as the motion of a pendulum or random such as the movement of a tire on a gravel road....
, proprioception
Proprioception

Proprioception ; from Latin proprius, meaning "one's own" and perception) is the sense of the relative position of neighbouring parts of the body....
 and fine touch (because the third-order neuron of the medial-lemniscal pathway cannot synapse in the cortex). It can also produce hemineglect, if it affects the non-dominant hemisphere.

It could also reduce nociception
Nociception

Nociception is defined as "the neural processes of encoding and processing noxious stimuli." It is the afferent activity produced in the peripheral and central nervous system by stimuli that have the potential to damage tissue....
, thermoception
Thermoception

Thermoception or thermoreception is the sense by which an organism perceives temperature. In larger animals, most thermoception is done by the skin....
 and crude touch, but since information from the spinothalamic tract
Spinothalamic tract

The spinothalamic tract is a sensory pathway originating in the spinal cord. It transmits information to the thalamus about pain, temperature, itch and crude tactition....
 is interpreted mainly by other areas of the brain (see insular cortex
Insular cortex

The insular cortex is a structure of the human brain. It lies deep to the brain's lateral surface, within the lateral sulcus which separates the temporal lobe and the parietal lobe dorsally....
 and cingulate gyrus
Cingulate gyrus

Cingulate gyrus is a gyrus in the medial part of the brain. It partially wraps around the corpus callosum and is limited above by the cingulate sulcus....
), it is not as relevant as the other symptoms.

See also


  • Brodmann area
    Brodmann area

    A Brodmann area is a region of the cerebral cortex defined based on its cytoarchitecture, or organization of cells.Brodmann areas were originally defined and numbered by Korbinian Brodmann based on the organization of neurons he observed in the cortex using the Franz Nissl staining....
  • List of regions in the human brain
    List of regions in the human brain

    anatomy regions of the brain are listed vertically, following hierarchies that are standard in neuroanatomy. Physiology, nervous system#vertebrate nervous systems and Embryology regions are listed horizontally in parentheses where appropriate....


Additional images


External links

- area 1 - area 2 - area 3