The researchers showed participants pictures of their loved one and pictures of another person they knew to study the activity in the reward center of the brain. They found that when viewing the loved one, the subjects experienced more activity in the dopamine-rich areas of the brain. They quantified the responses with questionnaires that helped them better understand the subjects.

What’s just as interesting is a study from 2012, which looked at people in long-term relationships using MRIs. The average length of the subjects’ relationships was 21.4 years. The people who reported that they still had strong feelings of romance and sexual attraction had similar levels of dopamine in their brains.

Finally, a 2009 review of studies made some conclusions that support the claims made by How to Respark the Romance. The review wanted to find out if it was possible to sustain romance in long-term relationships. What it concluded was that couples who reported strong romantic feelings, as typified by marital satisfaction, well-being, and high self-esteem, were satisfied in their relationships. Couples who lacked these traits or whose attachment trended toward obsession did not.

What we can take away from this is that there is some evidence to suggest that the presence of feel-good hormones is related to feelings of romance and passion. Hormonal levels can fluctuate, but dopamine levels are closely associated with the euphoric feeling of being in love.

A separate question is whether the techniques outlined in How to Respark the Romance work. We think that there’s some common-sense advice included – and that couples who are willing to work on their relationships are more likely to rekindle the romance than those who don’t try.