It has long been believed that people can't change their personalities, which are largely stable and inherited. But a review of recent research in personality science points to the possibility that personality traits can change through persistent intervention and major life events.

Personality traits, identified as neuroticism, extraversion, openness to experience, agreeableness and conscientiousness, can predict a wide range of important outcomes such as health, happiness and income. Because of this, these traits might represent an important target for policy interventions designed to improve human welfare.

The research, scheduled to be published in the December issue of American Psychologist, is the product of the Personality Change Consortium, an international group of researchers committed to advancing understanding of personality change. The consortium was initiated by Wiebke Bleidorn and Christopher Hopwood, University of California, Davis, professors of psychology who are also co-authors of the latest paper, "The Policy Relevance of Personality Traits." The paper has 13 other co-authors.

Policy change could be more effective

"In this paper, we present the case that traits can serve both as relatively stable predictors of success and actionable targets for policy changes and interventions," Bleidorn said.

"Parents, teachers, employers and others have been trying to change personality forever because of their implicit awareness that it is good to make people better people," Hopwood added.

But now, he said, strong evidence suggests that personality traits are broad enough to account for a wide range of socially important behaviors at levels that surpass known predictors, and that they can change, especially if you catch people at the right age and exert sustained effort. However, these traits also remain relatively stable; thus while they can change, they are not easy to change.

Resources are often invested in costly interventions that are unlikely to work because they are not informed by evidence about personality traits. "For that reason, it would be helpful for public policymakers to think more explicitly about what it takes to change personality to improve personal and public welfare, the costs and benefits of such interventions, and the resources needed to achieve the best outcomes by both being informed by evidence about personality traits and investing more sustained resources and attention toward better understanding personality change," researchers said.

Why focus on personality traits?

Research has found that a relatively small number of personality traits can account for most of the ways in which people differ from one another. Thus, they are related to a wide range of important life outcomes. These traits are also relatively stable, but changeable with effort and good timing. This combination—broad and enduring, yet changeable—makes them particularly promising targets for large-scale interventions. Both neuroticism and conscientiousness, for example, may represent good intervention targets in young adulthood. And certain interventions—especially those that require persistence and long-term commitment—may be more effective among conscientious, emotionally stable people. It is also important to consider motivational factors, as success is more likely if people are motivated and think change is feasible, researchers said.

Bleidorn and Hopwood said examples of important questions that could be more informed by personality science include: What is the long-term impact of social media and video games? How do we get children to be kinder and work harder at school? How do we help people acculturate to new environments? And, what is the best way to help people age with grace and dignity.(2019).