Tactile corpuscle
| Tactile corpuscle | |
|---|---|
 | |
 Papilla of the hand, magnified 350 times.
| |
| Details | |
| Location | Skin |
| Identifiers | |
| Latin | corpusculum tactus |
| TH | H3.11.06.0.00007 |
| FMA | 83605 |
| Anatomical terms of microanatomy | |
Tactile corpuscles or Meissner's corpuscles are a type of
Structure
Tactile corpuscles are encapsulated myelinated nerve endings,[3] surrounded by Schwann cells.[3] The encapsulation consists of flattened supportive cells arranged as horizontal lamellae surrounded by a connective tissue capsule. The corpuscle is 30–140 μm in length and 40–60 μm in diameter. A single nerve fiber meanders between the lamellae and throughout the corpuscle.[citation needed]
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 male prepuce.[4][5][6][7][8][9] More specifically, they are primarily located in glabrous skin just beneath the
Comparison with other receptors
lamellar corpuscles (the only other type of phasic tactile mechanoreceptor), which are located deeper in the dermis, and some free nerve endings .
Also, tactile corpuscles do not detect noxious stimuli; this is signaled exclusively by free nerve endings .
DevelopmentThe number of tactile corpuscles per square millimeter of human skin on the fingertips drops fourfold[clarification needed] 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.[11][clarification needed] FunctionTactile corpuscles are rapidly adapting mechanoreceptors. They are sensitive to shape and textural changes in exploratory and discriminatory touch. Their acute sensitivity provides the neural basis for reading Braille text. 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.[12] Any physical deformation of the corpuscle will cause phasic, the action potentials generated quickly decrease and eventually cease (this is the reason one stops "feeling" one's clothes).[12]
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.[citation needed] Additional images
References
Sources
External links
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