Proceedings of the Annual Meeting of the Cognitive Science Society

This paper first synthesizes research showing that (a) people reciprocate smiles, (b) smiling and being smiled at elevatesmood, and (c) elevated mood is associated with proclivity to smile. Collectively, these findings suggest that smiling iscontagious, i.e., smiles diffuse through a social network. The paper then presents experiments carried out to investigatehow various factors affect the contagiousness of smiling using an agent-based model in which smiling affects a moodvariable, which in turn affected proclivity to smile. The society consistently stabilized on a proportion of smilers, themagnitude of which was a function of social connectivity. Using previous data on the effect of weather and culturaldifferences on smile reciprocity, we simulated how these factors affect smile diffusion. Smile diffusion was greater in thesunny condition than the cloudy condition, and in the American condition than the Japanese condition, and both effectswere magnified by increased social connectivity.