Chances are that the person you were five years ago differs in some ways from the person you are today; your personality has likely changed. When psychology researchers try to explain why personalities change over time, they often focus on the major events in people's lives, such as graduating from school, getting married, or welcoming a new child to the world. These major events are believed to inspire personality changes, generally pushing people to become more agreeable, conscientious, and emotionally stable as they grow older.

However, there is so much more to people's lives than can be captured in a few big days, no matter how important those days may seem. Life is filled with thousands of everyday experiences—grabbing coffee with an old friend, finally finishing that difficult project at work, or enjoying a romantic date night with a partner. Though seemingly small, these everyday experiences "add up" over time, contributing most of the pages to people's life stories. How might they contribute to shaping their personalities?

Major Life Events, Everyday Experiences, and Personality Change

In a recent study, my colleagues and I set out to understand how major life events and everyday life experiences guide personality development. We analyzed data from a sample of nearly 5,000 adults, who agreed to complete monthly surveys about their Big Five personality traits: extraversion, agreeableness, conscientiousness, neuroticism, and openness to experience. In these surveys, participants responded to items like, "I have frequent mood swings" (neuroticism), and "I have a vivid imagination" (openness to experience) on a scale from 1 = strongly disagree to 5 = strongly agree.

After taking the personality surveys, participants were shown a list of 25 life events and asked to check "yes" or "no" to indicate whether they had experienced any of them during the past month. The list included several major events, such as starting college, graduating from school; getting promoted, demoted, or retiring; getting engaged, married, or divorced; finding out about a pregnancy, and having a child. The list also included a handful of "minor" life events—for instance, whether participants had a fight with a partner, whether their partner did something special for them, if they visited with friends or family they do not get to see often, or if they accomplished something they were proud of during the past month. For each event that participants checked "yes," they were asked to rate how positive or negative the experience was from their perspective.

As expected, some major life events, like getting engaged, married, or divorced, having a child, and retiring, were associated with large shifts in people's trajectories of personality growth—the person they became over time. For example, after getting divorced, people became more introverted and neurotic than we would have predicted based on their pre-event personality growth, but they also showed much larger increases in conscientiousness, agreeableness, and openness, becoming more organized and disciplined, warm and tender-hearted, and creative and imaginative.

But what about life's everyday moments? We found that everyday life experiences were associated with small but lasting personality changes that "added up" over time, leading to even greater personality changes than major events! For instance, people who accomplished just three things they were proud of during the two-year study period experienced larger cumulative changes in their personalities, on average, than people who started college (a major event) during the study. Similarly, people who reported that their partner did something special for them just three times over two years showed larger cumulative personality changes than people who got married.

Do People Respond in the Same Ways to Life Events?

Not everyone responded in the same way to the life events we studied. How positive or negative people perceived the event to be influenced how their personalities changed after the event occurred. Asking people to rate how positively they viewed each event was especially important for understanding how their levels of neuroticism changed over time—that is, how moody and prone to negative feelings (i.e., anxious, depressed, self-conscious) they tended to be. For example, some people were thrilled to visit with family and friends they do not get to see often, and generally reported lower levels of neuroticism after experiencing this event. For other people, however, there was clearly a reason they didn't see certain family members or friends very often. Their personality growth after the visit looked quite different from those who had a positive experience.


Our research shows that it's the "little," everyday experiences in life—and what you make of them—that matter most for understanding how personalities change over time. To improve your own personality, you do not need to wait for big events like marriage or graduating from college.  Instead, you could try to construct your life so that you have more small but positive moments.  Likewise, if you would like to help another person alter their personality, you could create small but meaningful experiences. Understanding the role of the small things can help us become the people we want to be.

For Further Reading

Dugan, K. A., Vogt, R. L., Zheng, A., Gillath, O., Deboeck, P. R., Fraley, R. C., & Briley, D. A. (2024). Life events sometimes alter the trajectory of personality development: Effect sizes for 25 life events estimated using a large, frequently assessed sample. Journal of Personality, 92(1), 130-146.

Keely A. Dugan is a postdoctoral fellow at the University of Minnesota, Twin Cities. She studies how individual differences, such as personality traits and attachment styles, change over time and in response to life experiences.