Happiness and Sadness Spread Just Like Disease

Wired highlights an impressive study that provides strong scientific evidence that emotions really are contagious. The implications could be profound both for personal behavior choices such as whom to associate with as well as for organizations.

Short excerpt from the Wired article: "Happiness proved less social than sadness. Each happy friend increased an individual’s chances of personal happiness by 11 percent, while just one sad friend was needed to double an individual’s chance of becoming unhappy.

Patterns fit disease models in another way. “The more friends with flu that you have, the more likely you are to get it. But once you have the flu, how long it takes you to get better doesn’t depend on your contacts. The same thing is true of happiness and sadness,” said David Rand, an evolutionary dynamics researcher at Harvard. “It fits with the infectious disease framework.”

The findings still aren’t conclusive proof of contagion, but they provide parameters of transmission rates and network dynamics that will guide predictions tested against future Framingham results, said Hill and Rand. And whereas the Framingham study wasn’t originally designed with emotional information in mind, future studies tailored to test network contagion should provide more sophisticated information."