You'll be giving her the opportunity to find someone, or perhaps to live a much more fulfilled life on her own.

London - How can you be certain a new partner is The One?

The question has occupied poets and lovers for centuries – but it seems the answer may lie with science, not soul.

According to a team of American researchers, it’s all in the way they make your brain light up.

Scientists at Brown University in Rhode Island used magnetic resonance imaging to observe which areas of people’s brains lit up as they thought about their partners.

Revisiting the images three years later, they found distinctive patterns of electrical activity in the brains of those whose relationships lasted.

To some, it might resemble the dystopian nightmares predicted by Orwell and Huxley, but for others the findings could help to avoid years with unsuitable partners. Professor Arthur Aron, a social psychologist at Stony Brook University in Long Island, New York, said: “If strong feeling is combined with signs they can regulate emotions, to see the partner positively and deal with conflict, then it seems to be really productive in staying with that person.”

The research, published in the journal Neuroscience Letters, says people in successful relationships had increased electrical activity in the caudate tail, an area of the brain which produces emotional responses to visual beauty.

They showed signs of stability, with less activity in a brain area related to addiction, while decreased activity in the medial orbitofrontal cortex suggested they were less critical.

Professor Aron said: “It does allow us to get at what is really going on inside someone aside from what they tell us.” - Daily Mail