A simple scan can predict how long your romance will last, neuroscientists claim.
Researchers from Brown University say a brain scan conducted at the very beginning of a relationship can determine whether a couple is destined for love and marriage or heartbreak.
Study leader Xiaomeng Xu performed fMRI (functional magnetic resonance imaging) scans on 18 Chinese men and women who were in the early stages of romantic love.
The participants were shown photos of their lovers, triggering a flurry of brain activity.
But while all of the participants showed scientific signs of love, the researchers identified subtle differences in each individual's brain scan.
Eighteen months later, the scientists contacted the study participants again to find out how their relationships were going.
They were shocked to discover a strong correlation between certain characteristics in the original brain scans and the participant's relationship status a year and a half later.
After another two years, 12 of the participants were contacted again. Six were still in the relationships they had started at the beginning of the study, and the other six weren't.
Despite the small sample study, Xu found a 'striking' link between brain activity in the first scan, and the length of the relationship.
The brain scans of participants whose relationships lasted showed lower levels of activity in the brain regions associated with judgement and 'sense of self'.
This indicates successful relationships are those in which people refrain from judging their new partners, even overlooking any negative traits.
Those in long-lasting unions also prioritised their lover's feelings and desires over their own.
But while ignoring your partner's flaws and putting their needs above yours bodes well at the beginning of a relationship, everything changes when it comes to marriage.
A study by Bianca Acevedo from Cornell University found that the happiest marriages were formed by individuals who had strong senses of self and realistic views of their partner's strengths and weaknesses.
Acevedo conducted fMRI scans of newlyweds who had been with their partners for an average of four years.
She compared their brain activity shortly after their marriages, to how happy they reported feeling 12 months later.
The participants who were happier a year after their weddings reported heightened activity in the regions of the brain associated with judgement and sense of self the exact opposite of the activity needed to start a successful relationship.
This suggests that while true love is blind and selfless in the early stages, it has to mature into a realistic partnership that nurtures each individual separately to last forever.
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