In physiology and perceptual psychology, (somatovisceral) sensitivity (from Latin sensibilis : perceptible, ability to feel) or sensation is understood to mean all sensory services of a living being that are not provided by specialized sensory organs such as the eye , ear , olfactory mucosa or tongue , but by sensors like free nerve endings that occur in different densities in the body. Sensitivity can be divided into visceral sensitivity (intestines) and somatic sensitivity, whereby a distinction is made within the last surface sensitivity (the "fifth sense", i.e. feeling through the skin including thermoception and nociception ) and depth sensitivity (bones, muscles and tendons).
Insofar as the somatosensory also the sensory includes the nerve system, may in addition to the following elementary nerve irritation and resulting from them sensations also the psychological part of the sensitivity in the feeling are included (as sensitivity in the general sense).
According to the nature of the stimulus
- Mechanoreception (pressure, vibration, stretching, etc.)
- Thermal reception (temperature)
- Nociception ( pain )
- Chemoreception ( sense of smell and taste , recording of O 2 and CO 2 - partial pressure and pH value in the blood to control the respiratory drive )
According to the origin of the stimulus
Exteroception : (closer) surroundings (recorded via skin and mucous membranes), insensitive: smell and taste
- Telezeption : wider environment (without an impressive example in humans), insensitive: seeing and hearing
- Interoception : the living being itself
After centripetal conduction
- lemniscal system (posterior cord and lemniscus medialis) as epicritical sensitivity ("fine perception", easy to localize)
- extralemniscal system (anterior strand ) as protopathic sensitivity ("coarse perception", difficult to localize)
After the interconnection in different core areas
- protopathic sensitivity : pain, temperature, and gross tactile sensations
- epicritical sensitivity : fine tactile sensations, two-point discrimination
- proprioceptive sensitivity : self-perception of the body (sensation of position, tension of muscles and tendons; receptors in muscles, tendons and joints)
- E. Bruce Goldstein: Sensation and Perception . Wadsworth, Pacific Grove 2002.
- Urs Boschung : Sensitivity. In: Werner E. Gerabek , Bernhard D. Haage, Gundolf Keil , Wolfgang Wegner (eds.): Enzyklopädie Medizingeschichte. De Gruyter, Berlin / New York 2005, ISBN 3-11-015714-4 , p. 1321.
- C. Hick: Physiology . Jungjohann Verlag, 1996.
- Schmidt, Thews, Lang: Human physiology . Springer Verlag, 2000.
- M. Trepel: Neuroanatomy . Urban & Fischer Verlag, 2004.