Tickling - the effect on the skin of a person or some species of animals. The tickling sensation caused by this is usually accompanied by general excitement with gusty laughter and a mass of involuntary, disordered reflected movements ( reflex ). In this case, the face usually turns red, the pulse and breathing become more frequent, and a person after prolonged tickling can become exhausted [1] .
In response to tickling, not only a man laughs, but also anthropoids and monkeys . True, their laughter is different from human, but, nevertheless, it is recognizable. Also at the end of the 20th century, data appeared that rats, when tickling, emit a certain ultrasonic signal with a frequency of 50 kHz . This signal can be considered as an analogue of laughter, as it is associated in rats with playing behavior [2] .
There are two types of tickling - knemmesis, that is, a sensation of light touches, and gargalysis, sensations of more severe effects on special "tickled" places on the body - under the armpits, along the ribs on the sides of the body, the soles of the feet and some others. Loud laughter, convulsive facial expressions, contraction of the muscles of the diaphragm accompany only the second type of tickling, gargalysis [2] .
To refer to people sensitive to tickling, the Russian language uses the stable phrase “afraid of tickling”, although the word “ticklish” (s) is also allowed. To date, there is no generally accepted scientific explanation for tickling, including the causes of this sensation and its role in the evolutionary process .
The most susceptible parts of the human body to tickling: the inner part of the auricles , the ribs , neck , sides, armpits , stomach , navel , inguinal zone, popliteal fossae, feet (especially the plantar part).
Content
- 1 Ticklish Theory
- 2 In History
- 3 In culture
- 4 Hypotheses on the nature of tickling
- 5 Self-tickling
- 6 notes
- 6.1 Sources
- 6.2 References
- 7 References
Tickling Theory
Currently, there are a number of explanations for the nature of tickling, but not one is basic. According to one hypothesis , tickling is a passive protective reaction of an organism that a person has suffered during evolution from animals of a lower class. It serves as a speedy detection of alien harmful insects on the skin. However, the main question about tickling remains unanswered: "Why does a person laugh when they tickle him?" Danger is fear. Laughter with fear is a rare occurrence caused by a high level of nervous strain. In the case of tickling, laughter is the rule. In addition, many organisms have a more powerful defense system called “pain”, which signals tissue damage or the development of pathological processes. However, the feeling of pain does not give rise to laughter.
At the same time, David Gartley , one of the founders of associative psychology , expressed the opinion that “laughter is an incipient cry, suddenly interrupted. If the same surprise that makes young children laugh intensifies a bit, they will cry. ” Tickling, he believed, causes laughter, because it is nothing but “instant pain and a feeling of pain, after which both of them instantly disappear, so that the onset and disappearance of pain alternate” [3] .
Moreover, if tickling was a protective reaction, then during the evolution this feeling should have been lost among the northern peoples due to the absence of dangerous insects in the cold latitudes. However, to date there is no evidence that sensitivity to tickling depends on race. .
An interesting feature of tickling is that it can be perceived as a pleasant sensation. Studies by American scientists have shown that the mechanism of people's perception of tickling is similar to sensations of pain, but with a different external reaction and implementation. If pain is tormenting, then in most children and some adults, a short tickling causes positive emotions .
At the same time, in the middle of the 18th century, researcher J. Beatty called laughter from tickling “animals”, and laughter caused by psychological reasons - “sentimental” (Beattie, 1779. P. 303, 305). Advocates of this view believe that tickling, being a direct stimulation of the nervous system , has nothing to do with humor and that the laughter it causes is purely reflex , something like reflex tears caused by onions.
Against the version of the protective function of tickling, the fact that the tickling sensation disappears very quickly in those who tickle also speaks. At the same time, the pain persists until the affected organ is completely cured, and in some cases it is constantly present (chronic or phantom pain) .
Thus, it is likely that tickling is nothing more than a “side effect” in the complex structure of the nervous system of complex organisms, which occurs at the borderline states between soft gentle touches and a stronger effect that causes pain. This is also confirmed by the fact that foci of increased sensitivity to tickling are located in places with the most delicate skin or which are the concentration of large nerve nodes .
In History
In medieval Europe and India, tickling was used as a special torture [2] .
In Culture
The landowner Anfisa Porfiryevna in “ Poshekhonskaya olden time ” M.E. Saltykova-Shchedrin as a sophisticated punishment ordered the guilty maid to tickle “to foam at the mouth” [2] .
New Zealand-based journalist David Farrier directed the Tickled documentary in 2016. Movie purchased for HBO and Magnolia Pictures .
Hypothetical Hypotheses
- Tickling is a reflex reaction of human skin to small animals and insects, which has not disappeared with the evolution of the species. American non-fiction writer I. Johnson believes that tickling is perceived by the skin and transmitted to the brain as a threat signal. Mrs. Johnson explains the laugh during tickling by the fact that “when the instant fright passes and the person realizes that there is no threat, he is relieved with nervous laughter.” The stronger the tickling, the greater the fright and the stronger the laughter.
- Tickling - built-in "generator of good mood." His task is to excite the internal resources of the body, which begin to work more actively replenishing the blood with various substances. Thus, tickling stabilizes mental instability, improves immunity , and charges the positive energies of a person’s emotions. However, scientists from the University of California have found that tickling may not help improve mood: experiments have shown that convulsive twitches of a tickled person have nothing to do with fun. Making sounds similar to laughter, a person, without realizing it, shows that this type of impact - tickling - is unpleasant for him and he would like to stop it.
- Tickling - a side effect that arose during the development of the human nervous system. Focused on all types of stimuli, including contact ones, the central nervous system has found a border “zone” between the main types of exposure: affection and pain.
Self-tickling
Aristotle also noticed that it’s impossible to tickle himself, and it seems that he never returned to this topic. Modern studies have confirmed the assumptions of Aristotle, explaining that it makes it impossible to self-tickle the cerebellum . This is due to the fact that the body understands what tickling arises from and realizes that there are no visible threats, because he performs the role of the aggressor. A person cannot tickle himself, because the consequences of independent movements are predicted and suppressed by the cerebellum in other parts of the brain. In people with an affected cerebellum, the mechanism for predicting movements and suppressing reactions to their own movements may be lost, in which case they can tickle themselves [4] . People with schizophrenia can also tickle themselves. [5] This occurs with a symptom of delirium of exposure, when it seems to patients that someone else controls the actions of their hands, but not them themselves [6] .
Notes
Sources
- ↑ Tickling // Brockhaus and Efron Encyclopedic Dictionary : in 86 volumes (82 volumes and 4 additional). - SPb. , 1890-1907.
- ↑ 1 2 3 4 Naimark E. The somatosensory cortex responsible for the “fear” of tickling in rats . Elements Date of treatment December 30, 2016.
- ↑ Hartley, 1749, cit. by: The Philosophy ..., 1987. R. 41-42
- ↑ Swaab Dick . XV.5. Implicit memory in the cerebellum // We are our brain: From the uterus to Alzheimer = Wij zijn ons brein. Van Baarmoeder tot Alzheimer / Per. with niderl. D.V. Silvestrova . - SPb. : Ivan Limbach Publishing House , 2014 .-- S. 364. - 544 p. - 3000 copies. - ISBN 978-5-89059-202-6 .
- ↑ Why is it impossible to tickle yourself? - BBC Russian Service
- ↑ Frith, Chris . When the system fails // Brain and soul: How nervous activity shapes our inner world = Making up the Mind: How the Brain Creates our Mental World / trans. from English P. Petrova. - M .: AST : Corpus , 2014 .-- S. 169-171. - 335 p. - ( Elements ). - 3000 copies. - ISBN 978-5-17-083015-2 .
Literature
- Tickling // Brockhaus and Efron Encyclopedic Dictionary : in 86 volumes (82 volumes and 4 additional). - SPb. , 1890-1907.