Do peoples’ personalities change after 30? They can, according to researchers who examined 132,515 adults age 21-60 on the personality traits known as the “Big Five”: conscientiousness, agreeableness, neuroticism, openness and extraversion.
These findings were reported in the May 2003 issue of the Journal of Personality and Social Psychology, published by the American Psychological Association (APA).
From this large sample of volunteers recruited and examined over the internet, lead researchers Sanjay Srivastava, PhD, and Oliver P John, PhD, working at the University of California at Berkeley, found that certain changes do occur in middle adulthood.
Conscientiousness increased throughout the age range studied, with the biggest increases in a person’s 20s; this trait is defined as being organized, planful, and disciplined, and past research has linked it to work performance and work commitments.
Agreeableness increased the most during a person’s 30s; this trait is defined as being warm, generous, and helpful, and has been linked to relationships and to prosocial behavior. Neuroticism declined with age for women but did not decline for men; this trait is defined in people who worry and are emotionally unstable. It has been linked to depression and other mental health problems. Openness showed small declines with age for both men and women. Finally, extraversion declined for women but did not show changes in men.
Both neuroticism and extraversion scores were higher for younger women than for younger men. But for both of these traits — and most strikingly for neuroticism — the apparent sex differences diminished with age.
Of the 132,515 participants, 54 percent were female, all lived in the U.S. or Canada, 86% were White and 14% were Asian, Black, Latino or Middle Eastern. A subset of the sample — 42,578 — were asked about their socioeconomic status. Of these participants, 405 (1%) said they were poor, 7,614 (18%) said they were working class, 23,024 (54%) said they were middle class and 10,718 (25%) said they were upper-middle class.
This study contradicts an often cited view that personality traits are genetically programmed to stop changing by early adulthood. There is considerable evidence against it, say the authors. In the study, “average levels of personality traits changed gradually but systematically throughout the lifespan, sometimes even more after age 30 than before. Increasing conscientiousness and agreeableness and decreasing neuroticism in adulthood may indicate increasing maturity – people becoming on the average better adapted as they get older, well into middle age.”
This information was originally published in May 2003
