Tactile corpuscle

Tactile corpuscle
Meissner's corpuscle
Skin.jpg
"Sensory nerve endings for touch" labeled at upper right.)
Gray936.png
Papilla of the hand, treated with acetic acid. Magnified 350 times.

A. Side view of a papilla of the hand.
a. Cortical layer.
b. Tactile corpuscle.
c. Small nerve of the papilla, with neurolemma.
d. Its two nervous fibers running with spiral coils around the tactile corpuscle.
e. Apparent termination of one of these fibers.

B. A tactile papilla seen from above so as to show its transverse section.
a. Cortical layer.
b. Nerve fiber.
c. Outer layer of the tactile body, with nuclei.
d. Clear interior substance.
Latin corpusculum tactus
Gray's subject #233 1061
MeSH Mechanoreceptors
Code TH H3.11.06.0.00007

Meissner's corpuscles (or tactile corpuscles) are a type of mechanoreceptor.[1] They are a type of nerve ending in the skin that is responsible for sensitivity to light touch. In particular, they have highest sensitivity (lowest threshold) when sensing vibrations lower than 50 Hertz. They are rapidly adaptive receptors.

Contents

Location

They are distributed on various areas of the skin, but concentrated in areas especially sensitive to light touch, such as the fingers, lips and nipples.[2][3][4][5][6][7] More particularly, they are primarily located just beneath the epidermis within the dermal papillae.[8]

Structure

Meissner's corpuscles are encapsulated unmyelinated nerve endings, which consist of flattened supportive cells arranged as horizontal lamellae surrounded by a connective tissue capsule. The corpuscle is between 30-140 μm in length and 40-60 μm in diameter.

A single nerve fiber meanders between the lamellae and throughout the corpuscle.

Age-related changes

The number of Meissner corpuscles per square millimeter of human skin on the fingertips drops fourfold between the ages of 12 and 50. The rate at which they are lost correlates well with the age-related loss in touch sensitivity for small probes (Thornbury and Mistretta, 1981).

Function

Any physical deformation in the corpuscle will cause an action potential in the nerve. Since they are rapidly adapting or phasic, the action potentials generated quickly decrease and eventually cease. (This is the reason one stops "feeling" one's clothes.)

If the stimulus is removed, the corpuscle regains its shape and while doing so (i.e.: while physically reforming) causes another volley of action potentials to be generated.

Because of their superficial location in the dermis, these corpuscles are particularly sensitive to touch and vibrations, but for the same reasons, they are limited in their detection because they can only signal that something is touching the skin.

Comparison with other receptors

Feelings of deep pressure (from a poke, for instance) are generated from Pacinian corpuscles (the only other type of phasic tactile mechanoreceptor), which are located deeper in the dermis, and some free nerve endings.

Also, Meissner's corpuscles do not detect pain; this is signalled exclusively by free nerve endings.

Eponym

Meissner's corpuscles were discovered by the anatomist Georg Meissner (1829–1905).

Additional images

  • Diagrammatic sectional view of the skin.

  • light micrograph

References

  1. ^ Paré, Michel; Joseph E. Mazurkiewicz, Allan M. Smith, and Frank L. Rice (2001-09-15). "The Meissner Corpuscle Revised: A Multiafferented Mechanoreceptor with Nociceptor Immunochemical Properties". The Journal of Neuroscience 21 (18): 7236–46. PMID 11549734. http://www.jneurosci.org/cgi/content/full/21/18/7236. 
  2. ^ Cauna, Nikolajs; Leonard L. Ross (1960-10-01). "The fine structure of meissner's touch corpuscles of human fingers" (PDF). The Journal of Cell Biology 8 (2): 467–82. doi:10.1083/jcb.8.2.467. PMC 2224947. PMID 13691669. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2224947. Retrieved 2010-05-07. 
  3. ^ Hoffmann, JN; Montag AG, Dominy NJ. (2004-11). "Meissner corpuscles and somatosensory acuity: the prehensile appendages of primates and elephants." (PDF). Anat Rec a Discov Mol Cell Evol Biol.: 1138–47. http://www.artsci.wustl.edu/~hpontzer/Courses/Hoffman%20et%20al%202004%20Anat%20Rec%20Meissners%20Corpuscles.pdf. Retrieved 2010-05-07. 
  4. ^ Bongiorno, Rita Bongiorno; Spyridoula Doukaki, Mario Aricò (2010-01-25). "Neurofibromatosis of the nipple-areolar area: a case series". Journal of Medical Case Reports 4 (22): 22. doi:10.1186/1752-1947-4-22. PMC 2823760. PMID 20205809. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2823760. Retrieved 2010-05-07. 
  5. ^ Martini / Bartholomew (1995/2010). Essentials of Anatomy and Physiology 3E. Pearson Benjamin Cummings. http://www.templejc.edu/dept/Biology/RHicks/biol2404Int/biol2404onl_ch5.htm. 
  6. ^ Afifi, Adel K.; Ronald Arly Bergman (1998/2005). Functional neuroanatomy: text and atlas. McGraw-Hill Professional. pp. 16. doi:10.1036/0071408126. ISBN 0070015899. 10.1036/0071408126. http://books.google.com/?id=_cWKT9-P9LAC&printsec=frontcover#v=onepage&q&f=false. 
  7. ^ "Nervous system - Touch". BBC. http://www.bbc.co.uk/science/humanbody/body/factfiles/touch/touch.shtml. Retrieved 2010-05-07. 
  8. ^ Winkelmann, R. K. (1959-01-21). "The Erogenous Zones: Their Nerve Supply and Significance". Proceedings of the Staff Meetings of the Mayo Clinic 34 (2): 39–47. PMID 13645790. http://www.cirp.org/library/anatomy/winkelmann/. 

External links

v · d · eNervous system, receptors: somatosensory system (GA 10.1059)
Medial lemniscus
Spinothalamic tract

M: PNS

anat(h/r/t/c/b/l/s/a)/phys(r)/devp/prot/nttr/nttm/ntrp

noco/auto/cong/tumr, sysi/epon, injr

proc, drug(N1B)

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Look at other dictionaries:

  • tactile corpuscle — n one of the numerous minute bodies (as a Meissner s corpuscle) in the skin and some mucous membranes that usu. consist of a group of cells enclosed in a capsule, contain nerve terminations, and are held to be end organs of touch called also… …   Medical dictionary

  • tactile corpuscle — n. any of various small, epidermal structures with nerve endings sensitive to touch or pressure …   English World dictionary

  • tactile corpuscle — noun : one of the numerous minute bodies in the skin and some mucous membranes that usually consist of a group of cells enclosed in a capsule, contain nerve terminations, and are held to be end organs of touch * * * an oval sense organ made of… …   Useful english dictionary

  • tactile corpuscle — an oval sense organ made of flattened cells and encapsulated nerve endings, occurring in hairless skin, as the tips of the fingers and toes, and functioning as a touch receptor. Also called Meissner s corpuscle. [1870 75] * * * …   Universalium

  • tactile corpuscle — tac′tile cor′puscle n. hic (lab cbl)psl an oval sense organ made of flattened cells and encapsulated nerve endings, occurring in hairless skin, as the tips of the fingers, and functioning as a touch receptor • Etymology: 1870–75 …   From formal English to slang

  • tactile corpuscle of Meissner — Meissner c …   Medical dictionary

  • tactile bud — or tactile corpuscle, any one of numerous minute, oval bodies which occur in sensitive parts of the skin and are involved with the sense of touch …   Useful english dictionary

  • corpuscle of Herbst — he(ə)rpst n any of several tactile organs that are found in birds and are related to Pacinian corpuscles Herbst Ernst Friedrich Gustav H. (1803 1893) German anatomist. Herbst spent his career teaching at the university at Göttingen. He also… …   Medical dictionary

  • tactile receptor — n an end organ (as a Meissner s corpuscle or a Pacinian corpuscle) that responds to light touch * * * a mechanoreceptor for the sense of touch; called also touch r …   Medical dictionary

  • tactile cell — n one of the oval nucleated cells (as in a Meissner s corpuscle) that are in close contact with the expanded ends of nerve fibers in the deeper layers of the epidermis and dermis of some parts of the body and prob. serve a tactile function * * *… …   Medical dictionary

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