The New York Times

…”In a separate study, 17 men and women who were passionately in love agreed to undergo scans to determine what lasting romantic love looks like in the brain. The subjects, who had been married an average of about 21 years, viewed a picture of their spouse. As a control, they also viewed photos of two friends.

“Compared with the reaction when looking at others, seeing the spouse activated parts of the brain associated with romantic love, much as it did when couples who had just fallen in love took the same test. But in the older couples, researchers spotted something extra: parts of the brain associated with deep attachment were also activated, suggesting that contentment in marriage and passion in marriage aren’t mutually exclusive.” (Emphasis added)

Source: New York Times, June 4, 2010