Tickling

Tickling is the act of touching a part of a body in a way that causes involuntary twitching movements or laughter.^[1] The word "tickle"^ⓘ evolved from the Middle English tikelen, perhaps frequentative of ticken, to touch lightly.^[1]

In 1897, psychologists G. Stanley Hall and Arthur Allin described a "tickle" as two different types of phenomena.^[2] One type is caused by very light movement across the skin. This type of tickle, called a knismesis, generally does not produce laughter and is sometimes accompanied by an itching sensation.

^ ^a ^b "Tickling". Dictionary.com. Retrieved 2012-05-27.
^ Hall, G. Stanley; Allin, Arthur (October 1897). "The psychology of tickling, laughing and the comic". The American Journal of Psychology. 9 (1): 1–42. doi:10.2307/1411471. JSTOR 1411471.

[dictionary.reference.com-1] "Tickling". Dictionary.com. Retrieved 2012-05-27.

[hallallin-2] Hall, G. Stanley; Allin, Arthur (October 1897). "The psychology of tickling, laughing and the comic". The American Journal of Psychology. 9 (1): 1–42. doi:10.2307/1411471. JSTOR 1411471.

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