Life events sometimes alter the trajectory of personality development: Effect sizes for 25 life events estimated...

Personality changes across the life span. Life events, such as marriage, becoming a parent, and retirement, have been proposed as facilitating personality growth via the adoption of novel social roles. However, empirical evidence linking life events with personality development is sparse. Most studies have relied on few assessments separated by long time intervals and have focused on a single life event. In contrast, the content of life is composed of small, recurrent experiences (e.g., getting sick or practicing a hobby), with relatively few major events (e.g., childbirth). Small, frequently experienced life events may play an important and overlooked role in personality development.

The present study examined the extent to which 25 major and minor life events alter the trajectory of personality development in a large, frequently assessed sample (N_sample  = 4904, N_assessments  = 47,814, median retest interval = 35 days).

Using a flexible analytic strategy to accommodate the repeated occurrence of life events, we found that the trajectory of personality development shifted in response to a single occurrence of some major life events (e.g., divorce), and recurrent, "minor" life experiences (e.g., one's partner doing something special).

Both stark role changes and frequently reinforced minor experiences can lead to personality change.