It’s often said that married couples grow more alike over the years. But can marriage really change your personality? New research by University of Georgia psychologist Justin Lavner and his colleagues shows that people’s personalities change in predictable ways within the first year and a half after tying the knot.
Psychologists are divided on the question of whether personality is innately determined by your genes or shaped by experiences in early childhood, with many believing it’s probably a combination of both nature and nurture. By adulthood, however, personality is usually established and doesn’t change greatly after that. Still, some research has shown that major life events can nudge personality in particular directions. For example, a strong introvert with a desire to teach can learn to be more extroverted in the classroom.
Marriage, of course, is one of the most important events in a person’s life. Since married couples have to find ways to get along on a daily basis, it’s perhaps not surprising that they’d experience changes in their personality as they adapt to partnered life. This is the hypothesis that Lavner and his colleagues tested.
For the study, 169 heterosexual couples were recruited to respond to questionnaires at three points in their marriage: 6, 12, and 18 months. This way, the researchers could detect trends in personality change. At each point, the couples (working individually) responded to two questionnaires, one assessing marital satisfaction and the other measuring personality.
The most widely accepted theory of personality is known as the Big Five. This theory proposes that there are five basic personality dimensions. The Big Five are usually remembered with the acronym OCEAN:
Openness. How open you are to new experiences. If you’re high in openness, you like trying new things. If you’re low in openness, you’re more comfortable with what’s familiar.
Conscientiousness. How dependable and orderly you are. If you’re high in conscientiousness, you like to be punctual and keep your living and working spaces tidy. If you’re low in conscientiousness, you don’t get uptight about deadlines, and you’re comfortable in your cluttered environment.
Extraversion. How outgoing you are. If you’re high in extraversion, you like socializing with lots of other people. If you’re low in extraversion (that is, introverted), you like having time to yourself.
Agreeableness. How well you get along with others. If you’re high in agreeableness, you’re easygoing and happy doing what everyone else is doing. If you’re low in agreeableness, you’ve got to have things your way, no matter what the rest of us want.
Neuroticism. How emotionally stable you are. If you’re high in neuroticism, you experience big mood swings and can be quite temperamental. If you’re low in neuroticism, your mood is relatively stable, and you live your life on an even keel.
When the researchers analyzed the data after 18 months of marriage, they found the following trends in personality change among the husbands and wives.
Openness. Both husbands and wives showed decreases in openness. Perhaps this change reflects their acceptance of the routines of marriage.
Conscientiousness. Husbands increased significantly in conscientiousness, whereas wives stayed the same. The researchers noted that women tend to be higher in conscientiousness than men, and this was the case with the husbands and wives in this study. The increase in conscientiousness for men probably reflects their learning the importance of being dependable and responsible in marriage.
Extraversion. Both husbands and wives became more introverted (lower in extraversion) over the first year and a half of marriage. Other research has shown that married couples tend to restrict their social networks compared to when they were single. This drop in extraversion probably reflects that trend.
Agreeableness. Both husbands and wives became less agreeable over the course of the study, but this downward trend is especially noticeable for the wives. In general, women tend to be more agreeable than men. What these data suggest is that these wives were learning to assert themselves more during the early years of marriage.
Neuroticism. Husbands showed a slight increase in emotional stability. However, the wives showed a much greater one. In general, women tend to report higher levels of neuroticism (or emotional instability) than men. It’s easy to speculate that the commitment of marriage had a positive effect on the wives’ emotional stability.
It probably comes as no surprise that marital satisfaction went downhill for both husbands and wives over the course of the study. By 18 months, the honeymoon was clearly over. However, the researchers did find that certain personality traits in husbands or wives predicted how much their marital satisfaction decreased.