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One of the parable studies of positive psychology is the investigation of Duchenne smiles and marital satisfaction reported by Harker and Keltner (2001). These researchers analyzed 114 pictures from the 1958 and 1960 yearbooks of a women's college in the Bay Area. All but three of the young women were smiling, but the smiles varied. Some showed what is called a Duchenne smile: a genuine, full-faced expression of happiness indexed by the degree to which the muscles surrounding one's eyes are contracted - crinkled, as it were. Others did not, smiling with only their mouths, displaying what are dubbed flight attendant smiles. On a 10-point scale reflecting the "Duchenne-ness" of these yearbook smiles, the average rating was 3.8.
The researchers chose these particular pictures for analysis because the women in them were participants in a long-term study of important life events. Specifically, the researchers knew - decades after the yearbook photos - whether the women were married and if they were satisfied with their marriage. As it turns out, the Duchenne-ness of their yearbook smiles predicted both of these outcomes. Young women who expressed positive emotions (happiness) in yearbook photos, and presumably in other venues of their lives, as middle-aged women had better marriages.
The skeptic might wonder if these results reflect the operation of some confound like physical attractiveness. Leaving aside the fact that physical beauty is not much of a route to happiness for people in general, prettiness did not account for the results in this particular sample. Harker and Keltner rated how attractive the pictures were, and this rating - largely independent of the Duchenne-ness rating - did not predict who had a satisfying marriage.
This is a provocative study, and I always mention it when giving a talk on happiness or positive psychology.
It was thus with interest that I read a more recent study that also looked at Duchenne smiles, in this case those shown in photographs of Major League Baseball players from the 1952 season (Abel & Kruger, 2010). The degree to which a player evidenced a Duchenne smile was coded, from no smile to partial (non-Duchenne) smile to full (Duchenne) smile. The percentages of players in each category were 42%, 43%, and 15%, respectively.
Analyses focused on the 150 players who had died as of June 2009, and the outcome measure of interest was longevity. Players who did not smile at all on average lived for 72 years. Those who smiled a bit on average lived for 75 years. And those with Duchenne smiles on average lived for 80 years. These are statistically significant differences, and possible confounds were controlled, including attractiveness. But these are also what I call significant significant differences. If we take these results at face value (no pun intended), a Duchenne smile is worth five to eight extra years of life ... happy years.
I have been a sports fan forever, and maybe it's just me, but it seems as if what it means to "put on a game face" has changed. Once upon a time, players in a variety of sports did their best to look confident and in control, whereas others tried to convey nothing (a poker face). But more recently, many athletes scowl and look incredibly angry. During the recent NCAA basketball tournament, I felt that I was watching a series of 40-minute unsychronized haka dances.
One's game face is a tactic used to intimidate the opponent and to bolster one's own self as a player. If a game face is simply a tactic, then who cares? But if one's game face also reflects one's typical approach to life - if the game face is also the life face - then I worry about today's athletes. I wish they smiled more often, if not during games and matches then at least before and after.
Mind you, the smiles were not causes of longevity in the study just described, simply markers of how these men presumably lived their lives, happily or not. Pasting a phony smile on your face is not going to make you live longer. But perhaps doing the sorts of things that positive psychologists have shown to produce lasting happiness might be beneficial.
And even if not, you'll have a better time more along the way, and so will everyone else who sees you.
References
Abel, E. L., & Kruger, M. L. (2010). Smile intensity in photographs predicts longevity. Psychological Science.
Harker, L. A., & Keltner, D. (2001). Expressions of positive emotion in women's college yearbook pictures and their relationship to personality and life outcomes across adulthood. Journal of Personality and Social Psychology.
Neither Ernie Banks (1931 - ) of the Chicago Cubs nor Roger Maris (1934 - 1985) of the New York Yankees played in the big leagues in the 1952 season, but their pictures seem to exemplify the difference between a Duchenne smile and a non-Duchenne smile. And Mr. Cub is still alive and ready to play two!
