According to a new study, grouches don't necessarily remain grouches for the rest of their lives.
Findings published in the journal Social Indicators Research suggest that people's personalities can change over time just as much as external factors like change in jobs or income, or marriage or divorce.
The researchers, of the University of Manchester's School of Psychological Sciences, said that the findings indicate we can increase our well-being not just through these actual external changes, but also through changes in our personalities.
"The focus of many wellbeing studies in economics is on how changes to our circumstances, such as a higher income, getting married or a different job might influence our wellbeing. The influence of our personality is often ignored in these types of studies in the belief that our personality can't or doesn't change," study researcher Dr. Chris Boyce said in a statement. "We show that personality can and does change and, not only is it more likely to change than an income increase, it contributes much more to changes in our wellbeing."
The study included 7,500 people from Australia who were asked at the beginning and end of a four-year period about their life satisfaction and personality. Their personality was measured with a questionnaire that looked at five elements of a personality: how open the person is to new experiences, how conscientious the person is, how extroverted the person is, how agreeable the person is and how neurotic the person is.
The researchers examined the differences in personality at the beginning and the end of the four-year period, and also looked at how these related to other changing factors, such as income, employment and whether the person got married.
They found that that the personalities of the people in the study changed just as much as the other outside factors over the four years, and the changes in personality were able to predict whether the study participants' life satisfaction also changed.
Past research has shown that personality is responsible for up to 35 precent of life satisfaction differences, the researchers said. For comparison, employment status and income each make up 4 percent, and marital status makes up 1 to 4 percent of life satisfaction differences.
Recently, a study in the journal Psychological Science showed that military service is a catalyst for personality change, Miller-McCune reported. That study included 1,300 men from Germany; 250 of them entered into the military. The researchers administered personality assessments four times over a six-year period.
"One of the goals of the military to break down the mentality you had in the outside world, and they're going to build you up as a soldier," the researcher of that study, Josh Jackson, of Washington University in St. Louis, told Miller-McCune."If you're going to find some life experience leading to changes in personality traits, it seems like one of the best environments for that to happen would be the military experience."
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