A dopamine-rich brain region associated with reward processing appears to play an important role in maintaining romantic relationships, according to new neuroimaging research. The study, published in Psychological Science, found evidence that the nucleus accumbens differently encodes representations of romantic partners and nonpartners.
Researchers Ryuhei Ueda and Nobuhito Abe wanted to use brain imaging techniques to better understand how emotional bonding is established and maintained in romantic relationships.
“I have been interested in the mystery of close interpersonal relationships since I was little: why and how do people build a long-term relationship with a significant other?” said Ueda, an assistant professor of cognitive neuroscience at Kyoto University. “In graduate school, I came across neuroimaging techniques that could tell us what is going on in our brain. I found that providing empirical evidence for those issues would be a tough but exciting work for me.”
Their study included 46 heterosexual men between 20 and 29 years old who were in a committed romantic relationship. The researchers used functional magnetic resonance imaging to record the men’s brain activity as they performed a task in which a successful response resulted in the presentation of an image showing a positive facial expression from either their partner or unfamiliar women.
Ueda and Abe found that anticipating positive feedback from a committed partner was associated with a unique pattern of activity in the nucleus accumbens. This was true regardless of the women’s attractiveness. The findings are in line with previous research, which have indicated that the nucleus accumbens plays a key role in establishing selective preferences toward one’s partner.
“Having an intimate romantic relationship is an important aspect of life for most people,” Ueda told PsyPost. “Our study has provided empirical evidence to reveal the neural mechanisms underlying relationship maintenance: the brain’s center of pleasure and addiction, the nucleus accumbens, encodes a relationship partner in a distinctive way from unfamiliar nonpartners. We think that the unique neural representations of a relationship partner might be associated with single-minded romantic relationships.”
But the study — like all research — includes some limitations.
“We think that longitudinal assessment is needed to reveal how the unique neural representations of a relationship partner are shaped and changed over time. Selective preference for a particular person can be observed even at initial meetings, which could motivate us to initiate the relationship,” Ueda said.
“Little is still known about precise neural mechanisms underlying this process. Also, numerous psychological studies have reported that relationship quality, such as commitment or satisfaction to the relationship, dynamically changes over time, which should be reflected in the neural representations.”
The study, “Neural Representations of the Committed Romantic Partner in the Nucleus Accumbens“, was published November 25, 2021.