In spite of the cliché that opposites attract, considerable research suggests couples — at least those who make long-term commitments — tend to have similar personalities. But are they attracted to one another because of their shared attitudes and beliefs, or do they grow to resemble one another over time?
Research just published in the journal Personality and Individual Differences points to the former conclusion. It suggests spousal similarity is more a matter of initial choice than gradual convergence — with the apparent exception of one personality trait.
A team led by Michigan State University psychologist Mikhila Humbad looked at 1,269 couples, who had been married for an average of just under 20 years. (The data was compiled by the Minnesota Center for Twin and Family Research.) Analyzing responses to a detailed Multidimensional Personality Questionnaire, the researchers examined whether the differences between husbands and wives narrowed depending upon the length of their marriage.
They found only “sporadic” evidence backing up that thesis, much of which “would be expected by chance alone.” They conclude the evidence argues against gradual convergence of personality as a compelling explanation for spousal similarity.
But they found spouses may influence one another in one important area.
“Aggression may be an exception to this general conclusion,” they write, “as the correlation between the difference score and marriage length was significant, and there was some indication a longer marriage length predicted a smaller difference score.”
Why might this be? “It is possible that individuals might reinforce each other’s aggressive tendencies due to hostile interpersonal exchanges, thereby promoting greater convergence over time,” they note.
So hostility on the part of one spouse can gradually bring out the hostility in another. Isn’t there a Stephen Sondheim song about that?