Photo: D. Corson/Corbis

Have you ever waited with excitement to share some amazingly good news with your partner, only to experience a surge of frustration and resentment when he or she barely reacts to your announcement? As a society, we place a huge amount of emphasis on being there for each other when we’re in need, but past research has actually shown that relationship satisfaction is influenced as much, if not more, by how we react to each other’s good news. Whereas emotional support from a partner when we’re down can have the unfortunate side-effect of making us feel indebted and more aware of our negative emotions, a partner’s positive reaction to our good news can magnify the benefits of that good fortune and make us feel closer to them.

Now an unusual brain-imaging study, published recently in Human Brain Mapping, has added to this picture, showing that the relationship satisfaction of longtime married elderly women is particularly related to the neural activity they show in response to their husbands’ displays of positive emotion, rather than negative emotion.

Psychologist Raluca Petrican at the Rotman Research Institute in Toronto and her colleagues at the University of Toronto recruited 14 women with an average age of 72 who’d been married for an average of 40 years. The researchers scanned these women’s brains as they watched some carefully prepared videos.

The silent ten-second videos showed each woman’s husband or a stranger displaying an emotion that mismatched the way the video clip was labeled in a one-sentence description on the screen. For example, the clip might show the husband smiling or laughing about a happy memory (such as the first house they bought), but the video was labeled misleadingly to suggest that the man was showing this emotion while talking about a sad memory (such as the time he got fired). Other videos showed the reverse mismatch: a negative emotional display, ostensibly shown while talking about the memory of a happy event.

Essentially, the videos were designed to make the women feel like they were seeing their husband or the stranger display a surprising emotional reaction that didn’t match their own feelings. The real-world equivalent would be a situation in which a husband is happy about something that his wife doesn’t “get”; and the questions are whether she will notice, and whether she is she more sensitive to this incongruent emotion in her husband than she would be in a stranger.

The first important finding to emerge from this setup was that the women showed enhanced overall brain activity — which suggests more mental and emotional neural processing — when watching the videos of their husbands compared with videos of the strangers, but only when the videos showed displays of surprisingly incongruent positive emotion. During the other types of videos (when the men appeared to display strangely negative emotion), the women’s brains showed just as much overall activity when watching a stranger as when watching their husband. In other words, their levels of whole-brain activity betrayed a special sensitivity to their husband’s (versus a stranger’s) unexpected positive emotion.

This jibes with the past research that’s shown it’s our response to our partners’ positive news that is all-important for relationship satisfaction. Remember that these women had been married for decades, so it’s likely that they and their husbands have been doing something right relationship-wise. The brain-imaging data suggest part of the reason might be that the women are acutely tuned to when their husbands are showing happiness that’s personal to them (rather than common to both partners).

This specific interpretation trips up a little with another main result: The women’s levels of marital satisfaction (according to a questionnaire) correlated with the amount of neural processing they showed in response to their husbands positive and negative emotion.

However, the special importance of how we respond to our partners’ positive emotion was supported by another key finding. Namely, women who scored higher on relationship satisfaction showed more brain activation in regions thought to contain mirror neurons (neurons that are considered important for empathy) when watching their spouses than they did when watching a stranger. Moreover, this enhanced mirror-neuron activity was especially present for the videos showing their husbands’ positive, rather than negative, emotion. Again, this appears to support the idea that marital happiness goes hand in hand with sensitivity to our partners’ positive emotion (though the researchers acknowledge a different or complementary interpretation that people in happy relationships have a suppressed response to their partners’ incongruent negative emotion).

We need to interpret these preliminary and complex findings with caution. And the exclusive focus on wives’ reactions to their husbands’ emotions does lend the study a slightly retro ’70s vibe — what about the way that husbands respond to their wives’ emotions, and the importance of that for the marital happiness of both parties? But that said, the results are tantalizing in suggesting that at a neural level, people in a long-term, committed relationship are especially sensitive to their partners’ positive emotion, and particularly so when this emotion is different from their own. This neatly complements other past research showing, for example, that people who are unable to differentiate their partners’ emotions from their own (they assume they’re the same), tend to be viewed by their partners as more controlling and smothering.

As a whole, this entire body of research gives pause for thought. How do you react when your partner arrives home on an emotional high? Would you only notice if you were feeling happy too?

Dr. Christian Jarrett, a Science of Us contributing writer, is editor of theBritish Psychological Society’s Research Digest blog. His latest book is Great Myths of the Brain.