If two people both decide to exercise and diet in order to lose 10 pounds, one person's success or failure should have no effect on how much effort the other person puts in. Right? Wrong.
We know from decades of research in social psychology, that people's calculations about how much effort to expend are significantly - and often unconsciously - influenced by the behavior of the people around them. For example, we know from studies on "social loafing" that when people work on "collective" tasks (an assembly line, a symphony orchestra), the more members of the team, the less effort each individual puts in.
In recent research, Kathleen McCulloch and colleagues took these ideas a step further. They wondered whether merely watching someone successfully complete a goal would lead people to be less motivated when they subsequently performed the same task. Here is what they did.
Participants were seated at computers and instructed to watch as various pictures of objects were flashed (one at a time) in different sections of the screen. While this was going on, a second window on the screen showed a video depicting the hands of a person who was unscrambling a series of scrambled words and writing down the answers. In one condition, the "hands" appeared to be having problems solving the scrambled words. Then the video ended abruptly. In another condition, the hands appeared to be solving the problems easily until the screen presented the words "The End." In other words, some participants - out of the corner of their eyes - watched a person succeed, while the others watched a person fail.
Next, all participants were asked to do the same unscrambling task that the hands had done. McCulloch and colleagues were interested in how many of the words, participants successfully completed.
They found that whether the hands had succeeded or failed directly predicted participants' own performance; when the hands failed to get all the way to the end, participants solved around 77% of the words. But when the hands succeeded (i.e. got all the way to the end of the task), the success rate decreased to 72% - a statistically significant difference.
One question that may come to mind is why weren't subjects in the success condition buoyed or "primed" by the success they witnessed? According to McCulloch and colleagues, they probably would have been if the hands hadn't gone all the way to completion. Instead, receiving the clear message that the hands had successfully completed the task appeared to prime the concept "Done." Just as there is evidence that we can "catch" other people's goals (Aarts, Gollwitzer, Hassin, 2004), it appears we can catch the completion or non-completion of those goals.
Might the relationship between the observer and the actor matter? Future research needs to examine this, but one interesting possibility is that this vicarious goal satiation effect will be even stronger between, say, members of a romantic couple than between two strangers. In other words, the more thinks that "his/her goals are my goals", the more satisfaction and sense of completion one should get when the partner succeeds. If so, this would lead to the ironic consequence that if you and partner share a goal to lose 10 pounds and your partner succeeds first, this will deflate, rather than invigorate, your own motivation.
McCulloch, K.C., Fitzsimons, G.M., Chua, S.N., & Albarracin, D. (2011).. Vicarious goal satiation. Journal of Experimental Social Psychology, 47, 685-688.