Cutaneous receptor

The cutaneous receptors are the types of sensory receptor found in the dermis or epidermis. They are a part of the somatosensory system. Cutaneous receptors include cutaneous mechanoreceptors, nociceptors (pain) and thermoreceptors (temperature).[1]

Types

The sensory receptors in the skin are:

Modalities

With the above-mentioned receptor types the skin can sense the modalities touch, pressure, vibration, temperature and pain. The modalities and their receptors are partly overlapping, and are innervated by different kinds of fiber types.

Cutaneous receptors
Modality Type Fiber type
Touch Rapidly adapting cutaneous mechanoreceptors (Meissner corpuscle end-organs
Pacinian corpuscle end-organs
hair follicle receptors
some free nerve endings)
Aβ fibers
Touch & pressure Slowly adapting cutaneous mechanoreceptors (Merkel and Ruffini corpuscle end-organs
some free nerve endings)
Aβ fibers (Merkel and Ruffini's), Aδ fibers (free nerve endings)
Vibration Meissners and Pacinian corpuscle end-organs Aβ fibers
Temperature Thermoreceptors Aδ fibers (cold receptors)
C fibers (warmth receptors)
Pain & Itch Free nerve ending nociceptors Aδ fibers (Nociceptors of neospinothalamic tract)
C fibers (Nociceptors of paleospinothalamic tract)

Morphology

Cutaneous receptors are at the ends of afferent neurons. They are usually encapsulated in elaborate cellular corpuscles. Generally, they are linked to collagen-fibre networks within the capsule. Ion channels are situated near these networks.

In sensory transduction, the afferent nerves transmit through a series of synapses in the central nervous system, first in the spinal cord or trigeminal nucleus, depending on the dermatomic area concerned. One pathway then proceeds to the ventrobasal portion of the thalamus, and then on to the somatosensory cortex.[2]

See also

References

  1. Lincoln R. J., Boxshall G. A. (1990): Natural history - The Cambridge illustrated dictionary. Cambridge University Press, Cambridge, ISBN 0 521 30551-9.
  2. Mader S. S. (2000): Human Biology. McGraw–Hill, New York, ISBN 0-07-290584-0.
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