@reiver

Contagious Laughter Only Contagious From Ingroup Members, Not From Outgroup Members

[L]aughter is contagious. Simply hearing laughter causes people to laugh (Provine, 1992). Until recently, most televised situation comedies used the contagious nature of laughter to improve viewers’ responses to on-screen humor by playing “canned” laughter or “laugh-tracks” following a punch line. However, researchers have found that canned laughter only improves the reaction to humorous material when the laughter is perceived as coming from fellow ingroup members rather than outgroup members (Platow et al, 2005). Thus, the contagious nature of laughter does not extend to outgroup members, which again underlines the social bonding function of laughter.

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Platow, M. J., Haslam, S. A., Both, A., Chew, I., Cuddon, M., Goharpey, N., Maur, J., Rosini, S., Tsekouras, A., & Grace, D.M. (2005). “It’s not funny if they’re laughing”: Self-categorization, social influence, and responses to canned laughter. Journal of Experimental Social Psychology, 41, 542-550

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Provine, R. R. (1992). Contagious laughter: Laughter is a sufficient stimulus for laughs and smiles. Bulletin of the Psychonomic Society, 30, 1-4.

-- Tyler F. Stillman , Roy F. Baumeister , C. Nathan DeWall

from "What's So Funny About Not Having Money? The Effects of Power on Laughter"

Quoted on Sat Jul 28th, 2012