FACTOID # 3: South Carolina has the highest rate of violent crimes and aggravated assaults per capita among US states.
 
 Home   Encyclopedia   Statistics   States A-Z   Flags   Maps   FAQ   About 
   
 
WHAT'S NEW
 

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

 

 

(* = Graphable)

 

 


Encyclopedia > Somatosensory system

The somatosensory system is a sensory system that detects experiences labeled as touch or pressure, temperature (warm or cold), pain (including itch and tickle), as well as proprioception, which is the sensations of muscle movement and joint position including posture, movement, visceral (internal) senses and facial expression. Visceral senses have to do with sensory information from within the body, such as stomach aches. Touch has several different meanings: Touch is physical contact, and a biological sense. ... This article is about the study of touching behaviour in humans. ... The human eye is the first element of a sensory system: in this case, vision, for the visual system. ... This article is about pressure in the physical sciences. ... For other uses, see Temperature (disambiguation). ... Look up Pain in Wiktionary, the free dictionary. ... For other uses, see Itch (disambiguation). ... The word tickle can refer to: tickling, the act of touching a part of the body lightly so as to cause involuntary laughter or contraction of the muscles; Trout tickling is a method of fishing by hand. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ... For other uses of Muscles, see Muscles (disambiguation). ... For other uses, see Joint (disambiguation). ... While not moving, a human can be in one of the following main positions. ... In a general sense, locomotion simply means active movement or travel, applying not just to biological individuals. ... Photographs from the 1862 book Mécanisme de la Physionomie Humaine by Guillaume Duchenne. ... Stomach ache is a non-medical term used to describe various forms of nausea or abdominal pain. ...


Touch may be considered one of five human senses; however, when a person touches something or somebody this gives rise to various feelings: the perception of pressure (hence shape, softness, texture, vibration, etc.), relative temperature and sometimes pain. Thus the term "touch" is actually the combined term for several senses. In medicine, the colloquial term "touch" is usually replaced with somatic senses, to better reflect the variety of mechanisms involved. This article is about the senses of living organisms (vision, taste, etc. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... This article is about pressure in the physical sciences. ... This article is about describing the shape of an object. ... Look up Soft in Wiktionary, the free dictionary. ... Look up texture in Wiktionary, the free dictionary. ... Oscillation is the variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. ... For other uses, see Temperature (disambiguation). ...

Contents

Anatomy

The somatosensory system is spread through all major parts of a mammal's body (and other vertebrates). It consists both of sensory receptors and sensory (afferent) neurones in the periphery (skin, muscle and organs for example), and further neurones within the central nervous system. Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria For the folk-rock band see The Mammals. ... Typical classes Petromyzontidae (lampreys) Placodermi - extinct Chondrichthyes (cartilaginous fish) Acanthodii - extinct Actinopterygii (ray-finned fish) Actinistia (coelacanths) Dipnoi (lungfish) Amphibia (amphibians) Reptilia (reptiles) Aves (birds) Mammalia (mammals) Vertebrata is a subphylum of chordates, specifically, those with backbones or spinal columns. ... In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. ... In nervous systems, afferent signals or nerve fibers carry information toward the brain. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ... A diagram showing the CNS: 1. ...


General somatosensory pathway

A somatosensory pathway typically has three long neurons[1]: primary, secondary and tertiary (or first, second, and third).

The cell body or soma is a structure in a neuron consisting of the main part of the cell and containing the nucleus. ... This is a dorsal root ganglion (DRG) from a chicken embryo (around stage of day 7) after incubation overnight in NGF growth medium stained with anti-neurofilament antibody. ... The term spinal nerve generally refers to the mixed spinal nerve, which is formed from the dorsal and ventral roots that come out of the spinal cord. ... The trigeminal ganglion (or Gasserian ganglion, or semilunar ganglion) occupies a cavity (Meckels cave) in the dura mater covering the trigeminal impression near the apex of the petrous part of the temporal bone. ... Cranial nerves Cranial nerves are nerves that emerge directly from the brain in contrast to spinal nerves which emerge from segments of the spinal cord. ... The cell body or soma is a structure in a neuron consisting of the main part of the cell and containing the nucleus. ... An axon, or nerve fiber, is a long slender projection of a nerve cell, or neuron, which conducts electrical impulses away from the neurons cell body or soma. ... The Spinal cord nested in the vertebral column. ... The brain stem is the stalk of the brain below the cerebral hemispheres. ... An axon, or nerve fiber, is a long slender projection of a nerve cell, or neuron, which conducts electrical impulses away from the neurons cell body or soma. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ... The thalamus (from Greek θάλαμος = bedroom, chamber, IPA= /ˈθæləməs/) is a pair and symmetric part of the brain. ... The ventral posterior nucleus is the somato-sensory relay nucleus in thalamus of the brain. ... The cerebellum (Latin: little brain) is a region of the brain that plays an important role in the integration of sensory perception and motor control. ... The cell body or soma is a structure in a neuron consisting of the main part of the cell and containing the nucleus. ... The lateral postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... The parietal lobe is a lobe in the brain. ...

Periphery

In the periphery, the somatosensory system detects various stimuli by sensory receptors, e.g. by mechanoreceptors. The sensory information (touch, pain, temperature etc.,) is then conveyed to the central nervous system by afferent neurones. There are a number of different types of afferent neurones which vary in their size, structure and properties. Generally there is a correlation between the type of sensory modality detected and the type of afferent neurone involved. So for example slow, thin unmyelinated neurones conduct touch whereas faster, thicker, myelinated neurones conduct pain. In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. ... Look up mechanoreceptor in Wiktionary, the free dictionary. ... A diagram showing the CNS: 1. ... In nervous systems, afferent signals or nerve fibers carry information toward the brain. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ... In nervous systems, afferent signals or nerve fibers carry information toward the brain. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ... Stimulus modality also sensory modality is one aspect of a stimulus. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ... Myelin is an electrically insulating phospholipid layer that surrounds the axons of many neurons. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ...


Spinal cord

In the spinal cord, the somatosensory system [2] includes ascending pathways from the body to the brain. One major target within the brain is the postcentral gyrus in the cerebral cortex. This is the target for neurones of the Dorsal Column Medial Lemniscal pathway and the Ventral Spinothalamic pathway. Note that many ascending somatosensory pathways include synapses in either the thalamus or the reticular formation before they reach the cortex. Other ascending pathways, particularly those involved with control of posture project to the cerebellum. These include the ventral and dorsal spinocerebellar tracts. Another important target for afferent somatosensory neurones which enter the spinal cord are those neurones involved with local segmental reflexes. For other uses, see Brain (disambiguation). ... For other uses, see Brain (disambiguation). ... The lateral postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... For other uses, see Cortex. ... The posterior column-medial lemniscus pathway is the sensory pathway responsible for transmitting fine touch and conscious proprioceptive information from the body to the cerebral cortex. ... The spinothalamic tract is the sensory pathway in the body that transmits pain, temperature, itch and crude touch. ... While not moving, a human can be in one of the following main positions. ... The cerebellum (Latin: little brain) is a region of the brain that plays an important role in the integration of sensory perception and motor control. ... The ventral spinocerebellar tract conveys proprioceptive information from the body to the cerebellum. ... The dorsal spinocerebellar tract (posterior spinocerebellar tract, Flechsigs fasciculus, Flechsigs tract) conveys proprioceptive information from the body to the cerebellum. ... In nervous systems, afferent signals or nerve fibers carry information toward the brain. ... The somatosensory system is the sensory system of somatic sensation. ... Neurons (also spelled neurones or called nerve cells) are the primary cells of the nervous system. ... The Spinal cord nested in the vertebral column. ... A reflex action or reflex is a biological control system linking stimulus to response and mediated by a reflex arc. ...


Brain

The primary somatosensory area in the human cortex is located in the postcentral gyrus of the parietal lobe. The postcentral gyrus is the location of the primary somatosensory area, the main sensory receptive area for the sense of touch. Like other sensory areas, there is a map of sensory space called a homunculus in this location. For the primary somatosensory cortex, this is called the sensory homunculus. Areas of this part of the human brain map to certain areas of the body, dependent on the amount or importance of somatosensory input from that area. For example, there is a large area of cortex devoted to sensation in the hands, while the back has a much smaller area. Interestingly, one study showed somatosensory cortex was found to be 21% thicker in 24 migraine sufferers, on average than in 12 controls[3], although we do not yet know what the significance of this is. Somatosensory information involved with proprioception and posture also targets an entirely different part of the brain, the cerebellum. The lateral postcentral gyrus is a prominent structure in the parietal lobe of the human brain and an important landmark. ... The parietal lobe is a lobe in the brain. ... The concept of a homunculus (Latin for little man, sometimes spelled homonculus, plural homunculi) is often used to illustrate the functioning of a system. ... A human brain. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ... The cerebellum (Latin: little brain) is a region of the brain that plays an important role in the integration of sensory perception and motor control. ...


Physiology

Initiation of probably all "somatosensation" begins with activation of some sort of physical "receptor". These somatosensory receptors, tend to lie in skin, organs or muscle. The structure of these receptors is broadly similar in all cases, consisting of either a "free nerve ending" or a nerve ending embedded in a specialised capsule. They can be activated by movement (mechanoreceptor), pressure(mechanoreceptor), chemical (chemoreceptor) and/or temperature. In each case, the general principle of activation is similar; the stimulus causes depolarisation of the nerve ending and an action potential is inititated. This action potential then (usually) travels inward towards the spinal cord. NERVE ENDINGS SUCK PENIS!!! ... A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. ... A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. ... A Chemosensor, also known as chemoreceptor, is a cell or group of cells that transduce a chemical signal into an action potential. ... In neuroscience, depolarization refers to the event a neuron undergoes when its membrane potential grows more positive with respect to the extracellular solution. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ... A. A schematic view of an idealized action potential illustrates its various phases as the action potential passes a point on a cell membrane. ... The Spinal cord nested in the vertebral column. ...


Technology

The new research area of haptic technology allows to provide touch sensation in virtual and real environments. This exciting new area has started to provide critical insights into touch capabilities.
This article is about haptic technology. ...


See also

Body image is a term which may refer to our perceptions of our own physical appearance, or our internal sense of having a body which is constructed by the brain. ... Cell signaling is part of a complex system of communication that governs basic cellular activities and coordinates cell actions. ... The traditional five senses in human kind are the senses of vision, hearing, taste, and smell, and touch. ... A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. ... Key goals of studies in the field of molecular cellular cognition (MCC) include the derivation of explanations of cognitive processes that integrate molecular, cellular, and behavioral mechanisms, and finding mechanism and treatments for cognitive disorders. ... A nociceptor is a sensory receptor that sends signals that cause the perception of pain in response to potentially damaging stimulus. ... A muscle spindle is a specialized muscle structure innervated by both sensory and motor neuron axons. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ...

Notes

  1. ^ Saladin KS. Anatomy and Physiology 3rd ed. 2004. McGraw-Hill, New York.
  2. ^ Nolte J.The Human Brain 5th ed. 2002. Mosby Inc, Missouri.
  3. ^ "Thickening in the somatosensory cortex of patients with migraine." Alexandre F.M. DaSilva, Cristina Granziera, Josh Snyder, and Nouchine Hadjikhani. Neurology, Nov 2007; 69: 1990 - 1995.

References

  • Robles-De-La-Torre G. The Importance of the Sense of Touch in Virtual and Real Environments. IEEE Multimedia 13(3), Special issue on Haptic User Interfaces for Multimedia Systems, pp. 24-30 (2006).

External links

  • 'Somatosensory & Motor research' (Informa Healthcare)
  • Overview
  • Somatic vs. Special senses
The nervous system is a highly specialized network whose principal components are nerves called neurons. ... The human eye is the first element of a sensory system: in this case, vision, for the visual system. ... This article is about the senses of living organisms (vision, taste, etc. ... The traditional five senses in human kind are the senses of vision, hearing, taste, and smell, and touch. ... The visual system is the part of the nervous system which allows organisms to see. ... In psychology, visual perception is the ability to interpret information from visible light reaching the eyes. ... The auditory system is the sensory system for the sense of hearing. ... Hearing (or audition) is one of the traditional five senses, and refers to the ability to detect sound. ... A Chemosensor, also known as chemoreceptor, is a cell or group of cells that transduce a chemical signal into an action potential. ... The olfactory system is the sensory system used for olfaction. ... Olfaction (also known as olfactics) refers to the sense of smell. ... The gustatory system is the sensory system that uses taste buds (or lingual papillae) on the upper surface of the tongue to provide information about the taste of food being eaten. ... Taste (or, more formally, gustation) is a form of direct chemoreception and is one of the traditional five senses. ... A nociceptor is a sensory receptor that sends signals that cause the perception of pain in response to potentially damaging stimulus. ... A thermoreceptor is a sensory receptor that responds to temperature, primarily within the innocuous range. ... The vestibular system, or balance system, is the sensory system that provides the dominant input about movement and equilibrioception. ... A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. ... This article is about pressure in the physical sciences. ... Oscillation is the variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. ... // Proprioception (PRO-pree-o-SEP-shun (IPA pronunciation: ); from Latin proprius, meaning ones own and perception) is the sense of the relative position of neighbouring parts of the body. ... In a sensory system, a sensory receptor is a structure that recognizes a stimulus in the internal or external environment of an organism. ...

  Results from FactBites:
 
Sensory system - Wikipedia, the free encyclopedia (619 words)
In the memory-prediction framework, Jeff Hawkins mentions a correspondence between the six layers of the cerebral cortex and the six layers of the optic tract of the visual system.
Somatosensory Area 1, or S1, is for touch and proprioception in the somatosensory system.
The somatosensory system feeds the Brodmann Areas 3, 1 and 2 of the primary somatosensory cortex.
Somatosensory system - Wikipedia, the free encyclopedia (302 words)
The somatosensory system is the sensory system of somatic sensation.
The primary somatosensory area in the human cortex is located in the postcentral gyrus (Parietal Lobe).
Areas of this part of the human brain map to certain areas of the body, dependant on the amount or importance of somatosensory input from that area.
  More results at FactBites »

 
 

COMMENTARY     


Share your thoughts, questions and commentary here
Your name
Your comments

Want to know more?
Search encyclopedia, statistics and forums:

 


Press Releases |  Feeds | Contact
The Wikipedia article included on this page is licensed under the GFDL.
Images may be subject to relevant owners' copyright.
All other elements are (c) copyright NationMaster.com 2003-5. All Rights Reserved.
Usage implies agreement with terms, 1022, m