Acutaneous receptor is asensory receptor found in the skin that provides information abouttemperature,touch (including vibration and pain),spatial orientation,pressure (stretching or squeezing), andmetabolic circumstances (including those induced by external chemical substances). The main four types of cutaneous receptors aretactile corpuscles,bulbous corpuscles,Pacinian corpuscles, andMerkel nerve endings, although the latter do not qualify as sensory corpuscles in the narrow sense.[1]
The sensory receptors in the skin are:
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 offiber types.
| Modality | Type | Fiber type |
|---|---|---|
| Touch | Rapidly adapting cutaneous mechanoreceptors (tactile corpuscles Pacinian corpuscles hair follicle receptors somefree nerve endings) | Aβ fibers |
| Touch and pressure | Slowly adapting cutaneous mechanoreceptors (Merkel nerve ending andbulbous corpuscles somefree nerve endings) | Aβ fibers (Merkel and Ruffini's),Aδ fibers (free nerve endings) |
| Vibration | Tactile corpuscles andPacinian corpuscles | Aβ fibers |
| Temperature | Thermoreceptors | Aδ fibers (cold receptors) C fibers (warmth receptors) |
| Pain and Itch | Free nerve endingnociceptors | Aδ fibers (Nociceptors ofneospinothalamic tract) C fibers (Nociceptors ofpaleospinothalamic tract) |
Cutaneous receptors are at the ends of afferent neurons. works within the capsule. Ion channels are situated near these networks.
Insensory transduction, theafferent nerves transmit through a series ofsynapses in thecentral nervous system, first in thespinal cord, the ventrobasal portion of thethalamus, and then on to thesomatosensory cortex.[2]