By Matthew Warren

Researchers have long known that people who are more extraverted tend to be happier, leading some to suggest that encouraging extraverted behaviour could improve wellbeing. Last year we reported on the first trial of such an intervention, which found that acting like an extravert for a week led to an increase in positive emotions in certain people. Now a second study appears to have replicated that result — and shown that behaving like an introvert may also reduce wellbeing.

In the new study, published in the Journal of Experimental Psychology: General, Seth Margolis and Sonja Lyubomirsky at the University of California, Riverside, asked 131 participants to alter their behaviour over a two week period to be more extraverted or introverted. For one week, participants were encouraged to act as “talkative”, “assertive” and “spontaneous” as possible; for the other, they were told to act “deliberate”, “quiet” and “reserved” (all participants completed both weeks, but half began with the extraverted week while the others began with with the introverted week).

To encourage the participants to actually alter their behaviour, the researchers asked them to list five specific changes they planned on making, and then sent them periodic reminders of their task throughout the study. At various points across the two weeks, the participants completed scales measuring their experience of positive and negative emotions and others aspects of wellbeing, as well as their personality traits.

Compared to baseline levels at the start of the study, participants experienced more positive emotions during the extraverted week — and also showed reduced positive emotions during the introverted week. Some other measures of wellbeing, such as feelings of connectedness and flow (the experience of being immersed in — and enjoying — an activity) were also boosted by acting extraverted and reduced by acting introverted.

However, these results didn’t hold for all measures of wellbeing. For instance, participants seemed to have reduced negative emotions compared to baseline during both interventions (although the exact pattern of results differed depending on whether participants began with the extraverted or introverted week).

The results add to the small, albeit growing, body of evidence that acting like an extravert can improve certain aspects of wellbeing — particularly measures of positive emotion. But the authors suggest that their biggest contribution is to show that acting like an introvert can also have an effect. “Given that introversion is generally not regarded as desirable or advantageous in U.S. culture … we believe our most compelling results are those showing that well-being decreases can be substantial when people act more introverted than usual,” they write.

Still, it seems too soon to suggest that we should we all begin behaving like extraverts. The study the Digest reported on last year found that people who had high trait levels of introversion didn’t report the same benefits of acting like an extravert as the rest of the participants, and actually became more fatigued and experienced more negative emotions. On the other hand, the new paper found that baseline levels of extraversion and introversion didn’t affect the results – but it’s still clear that researchers need a better understanding of how individual differences could influence the effectiveness of the intervention.

And it will also be important to figure out which behaviours are actually causing the increases or decreases in wellbeing reported in these studies. It’s not yet clear whether it was being more “talkative”, “assertive”, or “spontaneous” that resulted in an increase in wellbeing in the extraverted week, for instance, and the researchers suggest examining changes in a more specific sub-set of extraverted behaviours in the future. “We hope that research from our and others’ laboratories encourages future investigators to test the potential of behavioral interventions to spur both personality change and well-being gains,” they conclude.

– Experimental manipulation of extraverted and introverted behavior and its effects on well-being

Matthew Warren (@MattbWarren) is Editor of BPS Research Digest