A brain "in love" is markedly different from other brains, says research claiming to be the first empirical evidence of love-induced alterations in the brain's functional architecture.

The study could pave the way for a brain scan that could be used as a love test.

By tracking neural activity of participants including those in love, those out of love and those never in love, the "love map" pieced together by researchers in China and New York have pinned down the physical effects of love in the brain.

Scientists recruited 100 students from Southwest University in Chongqing, China, who were divided into three groups according to their relationship status: an "in-love" group, an "ended-love" group, who had recently ended loving relationships; and a "single" group, who had never been in love.

Participants were told not to think of anything while their brain MRI scans were taken.

Those from the "in love" category showed increased activity in several areas of the brain, including in parts that deal with reward, motivation, and emotion regulation, as well as in the social cognition network.

The amount of activity in some parts positively correlated with the duration of love for the "in love" group.

For the "ended love" group, the longer they had been out of love, the lower the amount of activity detected in these areas of the brain.

The work, titled "Love-related changes in the brain: a resting-state functional magnetic resonance imaging study", throws light on the underlying neurophysiological mechanisms of romantic love by investigating intrinsic brain activity, said the researchers.

The study, led by Professor Xiaochu Zhang of the University of Science and Technology of China, in Hefei, establishes that romantic love also affects the functional architecture of the brain.

Published in Frontiers in Human Neuroscience, it was jointly compiled by scientists from Southwest University, the University of Science and Technology of China and from the Icahn School of Medicine at Mount Sinai, New York.

Science of love

Establishing a scientific basis to love has seen quite some amount of research, proving why a failure in love often leads to much emotional stress and depression.

Back in 2010 a groundbreaking study by Syracuse University Professor Stephanie Ortigue called "The Neuroimaging of Love," revealed that falling in love not only delivers the same euphoric feeling as using cocaine, but also affects intellectual areas of the brain.

Other researchers have found blood levels of nerve growth factor also increased in couples who had just fallen in love.

University of Louisville professors, meanwhile, have been trying to get to the bottom of altruistic love or compassionate love as against romantic love.

Research from UCLA and the University of North Carolina has shown compassion has health benefits for people with lower rates of cellular inflammation, which is associated with diseases and cancer.