cutaneous touch receptor

Examples of cutaneous touch receptor in the following topics:

• Classification of Receptors by Location

  • Some sensory receptors can be classified by the physical location of the receptor.
  • Receptors are sensitive to discrete stimuli and are often classified by both the systemic function and the location of the receptor.
  • Our skin includes touch and temperature receptors, and our inner ears contain sensory mechanoreceptors designed for detecting vibrations caused by sound or used to maintain balance.
  • While the cutaneous touch receptors found in the dermis and epidermis of our skin and the muscle spindles that detect stretch in skeletal muscle are both mechanoreceptors, they serve discrete functions.
  • In both cases, the mechanoreceptors detect physical forces that result from the movement of the local tissue, cutaneous touch receptors provide information to our brain about the external environment, while muscle spindle receptors provide information about our internal environment.

• Tactile Sensation

  • Touch is sensed by mechanoreceptive neurons that respond to pressure in various ways.
  • Cutaneous mechanoreceptors are located in the skin, like other cutaneous receptors.
  • They provide the senses of touch, pressure, vibration, proprioception, and others.
  • They are rapidly adaptive receptors.
  • Describe how touch is sensed by mechanoreceptive neurons responding to pressure

• Cutaneous Sensation

  • The somatosensory system is composed of the receptors and processing centers to produce the sensory modalities, such as touch and pain.
  • The somatosensory is the system of nerve cells that responds to changes to the external or internal state of the body, predominately through the sense of touch, but also by the senses of body position and movement.
  • While touch is considered one of the five traditional senses, the impression of touch is actually formed from several diverse stimuli using different receptors:
  • Mechanoreceptors are sensory receptors that respond to pressure and vibration.
  • The Merkel receptor is a disk-shaped receptor located near the border between the epidermis and dermis.

• Classification of Receptors by Stimulus

  • Sensory receptors can be classified by the type of stimulus that generates a response in the receptor.
  • During touch, mechanoreceptors in the skin and other tissues respond to variations in pressure.
  • Cutaneous receptors are sensory receptors found in the dermis or epidermis.
  • Encapsulated receptors consist of the remaining types of cutaneous receptors.
  • A tonic receptor is a sensory receptor that adapts slowly to a stimulus, while a phasic receptor is a sensory receptor that adapts rapidly to a stimulus.

• Somatosensation: Pressure, Temperature, and Pain

  • The human sense of touch is known as the somatic or somatosensory system.
  • Touch is the first sense developed by the body, and the skin is the largest and most complex organ in the somatosensory system.
  • Touch receptors in the skin have three main subdivisions: mechanoreception (sense of pressure), thermoreception (sense of heat) and nociception (sense of pain).
  • The receptors in the skin, also called cutaneous receptors, tell the body about the three main subdivisions mentioned above: pressure and surface texture (mechanoreceptors), temperature (thermoreceptors), and pain (nociceptors).
  • The first type is a rapidly transmitted signal with a high spatial resolution, called first pain or cutaneous pricking pain.

• Sensory Modalities

  • The cutaneous somatosensory system detects changes in temperature.
  • Neurologists test this sense by telling patients to close their eyes and touch their own nose with the tip of a finger.
  • Proprioception and touch are related in subtle ways, and their impairment results in deep and surprising deficits in perception and action.
  • The three types of pain receptors are cutaneous (skin), somatic (joints and bones), and visceral (body organs).
  • It was previously believed that pain was simply the overloading of pressure receptors, but research in the first half of the 20th century showed that pain is a distinct phenomenon that intertwines with all of the other senses, including touch.

• Classification of Nerves

  • A-alpha fibers are the primary receptors of the muscle spindle and golgi tendon organ.
  • A-beta fibers act as secondary receptors of the muscle spindle and contribute to cutaneous mechanoreceptors.
  • The Schwann cell keeps them from touching each other by squeezing its cytoplasm between the axons.

• Integration of Signals from Mechanoreceptors

  • The configuration of the different types of receptors working in concert in the human skin results in a very refined sense of touch .
  • The nociceptive receptors (those that detect pain) are located near the surface.
  • Small, finely-calibrated mechanoreceptors (Merkel's disks and Meissner's corpuscles) are located in the upper layers and can precisely localize even gentle touch.
  • The large mechanoreceptors (Pacinian corpuscles and Ruffini endings) are located in the lower layers and respond to deeper touch.
  • Touch receptors are denser in glabrous skin (the type found on human fingertips and lips, for example), which is typically more sensitive and is thicker than hairy skin (4 to 5 mm versus 2 to 3 mm).

• What is Skin?

  • The cutaneous membrane is the technical term for our skin.
  • Functions of the epidermis include touch sensation and protection against microorganisms. 
  • These signals include touch, temperature, pressure, pain, and itching.

• Art and Illusion

  • In short, audio illusions highlight areas where the human ear and brain, as organic and makeshift tools, differ from perfect audio receptors (for better or for worse).
  • Tactile illusions are illusions that exploit the sense of touch.
  • Some tactile illusions require active touch (such as the movement of the fingers or hands), whereas others can be evoked passively (for example, with external stimuli that press against the skin).
  • One of the best known passive tactile illusions is the cutaneous rabit illusion, in which a sequence of taps at two separated skin locations results in the perception that intervening skin regions were also tapped.