Most psychologists agree that a person's basic personality—whether they are an introvert or extrovert, for example—remains the same throughout life. What we might see as personality changes are actually just responses to external factors, such as getting a job, getting married or becoming a parent. That said, research does indicate that our personalities become more solidified, or stable, as we get older. 
 
 That change is not linear, however. New research indicates that our personalities become increasingly stable as our 20s melt into our 30s, 40s and even 50s, but that that stability then often begins to taper off in old age, Research Digest reports. 
 
 Researchers in New Zealand recruited 4,000 men and women aged 20 to 80 to complete a personality questionnaire twice, with a gap of two years in between. The survey measured a person's honesty-humility factor as well as five major personality traits: extraversion, agreeableness, conscientiousness, neuroticism and openness to experience, Research Digest writes. They compared how people's scores varied between years, and analyzed how all of the participants personalities related to one another, depending on age. 
 
 Most people's personalities were generally stable, they found, but the stability of those trait followed a bell curve over time, peaking at middle-age and then dropping again. For certain traits—conscientiousness, openness to experience, and honesty-humility—Research Digest writes, the oldest participants' personality stability matched those of the youngest. 
 
 Other interesting finds included "domain specific" variations, or ones that seem to be linked to what a person is dealing with at a particular point in their life. People in their 30s, for example, showed high levels of neuroticism, but by the time they reached their 50s that had tapered off and had been replaced by conscientiousness, openness and honesty-humility. ||||| A new study shows that your friends’ assessments of your personality may offer insight into how long you’ll live. The findings are published in the journal Psychological Science. 
 
 Scientists have long known that personality is a strong indicator of future health and longevity. For example, traits such as openness and agreeableness are linked to longer lives, while neuroticism and pessimism are linked to shorter, unhealthier lives. 
 
 However, since self-reports of personality are notoriously biased, researchers wanted to know if the opinions of friends would give a more accurate picture of a person’s mortality; it turns out they do. 
 
 For the study, psychological scientist Joshua Jackson of Washington University in St. Louis and colleagues analyzed data from the Kelly/Connolly Longitudinal Study. The research began back in the 1930s, when 600 participants in their mid-20s — 300 engaged couples — volunteered for a study of personality and new marriages. 
 
 The questionnaire included personality ratings given by five close friends — most of them members of the wedding party. It also included self-ratings of personality. 
 
 Seventy-five years later (last year), the scientists tracked down most of the original volunteers or their obituaries. They then compared the friends’ views with the volunteers’ views of themselves to see which was a better predictor of life and death. 
 
 According to the findings, the men’s self-reports were fairly accurate at predicting life and death, though not as good as their friends’ assessments. The women’s self-reports, however, were fairly inaccurate at predicting mortality. 
 
 For all the young participants who were just entering adulthood 75 years ago, their friends picked up on traits in their personalities more strongly related to health and well-being — insights that could prove relevant to public health policy today. 
 
 For example, young men who were described by their groomsmen as conscientious and open to experience went on to live the longest lives. 
 
 Conscientiousness and openness are two of the so-called Big Five personality traits. Conscientious people are dutiful, disciplined, organized, and dependable, while open people are intellectually curious and inventive. Men with these two traits lived longer — or alternatively, those lacking these traits died earlier. 
 
 Females had a different set of traits linked to longevity. High levels of agreeableness and emotional stability — as identified by their bridesmaids and other close friends — were linked to the longest lives. Emotional stability is the opposite of neuroticism — the tendency toward anger and anxiety and depression — while agreeableness encompasses cooperation and compassion. 
 
 The findings should be viewed in historical context, however, say the scientists. The participants were coming of age in the 1930s, when the positive traits were indicative of a supportive and easy-going wife — typically considered the emotional leader of the family. 
 
 Source: Association for Psychological Science 
 
 
 
 
 
 Group of friends talking photo by shutterstock.
– There's no doubt about it: The human body goes through major changes in youth and old age. And these biological and social changes may be the reasons behind what researchers are calling less stable personalities at those life stages. In fact, according to a study of almost 4,000 New Zealanders between the ages of 20 and 80, the stability of one's personality increases through youth and into middle age and peaks in our 50s, before we slide back into less stable versions of ourselves, reports Research Digest. As the Smithsonian puts it, "in some ways, our 80-year-old selves mirror our 20-year-old selves." Some traits peaked at different times; the most stable traits in one's 30s are extraversion and neuroticism, while in the late 40s and early 50s it is openness, honesty-humility, and conscientiousness. The only trait that showed "gradually reduced stability" throughout life was agreeableness; apparently we are simply less and less agreeable as we pack the years on. Still, one's most basic personality—introvert vs. extrovert, for example—tends to remain consistent throughout one's life, even if the stability of traits waxes and wanes, notes the Smithsonian. (Other researchers have even calculated the country's most extroverted city.)