Summary: Researchers have identified neural and genetic factors linked to romantic love and its maintenance in newlyweds. Sustaining romantic love engages not only subcortical reward regions but also higher-order cortical areas. Genetic variability in systems tied to dopamine, vasopressin, and oxytocin appears to influence the tendency to maintain romantic attachment.
Source: UC Santa Barbara
If you’ve ever been newly married, you know the rush of excitement that comes with saying “I do” and beginning life with a partner. That feeling—romantic love in contemporary Western culture—has long been described as “chemistry.” New research from UC Santa Barbara puts some scientific detail behind that phrase.
For the first time, researchers have combined functional MRI (fMRI) with genetic analysis to examine the neural and genetic correlates of romantic love maintenance in newlyweds. Bianca Acevedo and colleagues scanned 19 first-time newlyweds (11 women and 8 men) around the time of their weddings and again one year later. The study reveals that sustaining romantic love engages brain reward circuits as well as higher-level cognitive regions and that individual genetic differences in neurochemical systems can influence this process.
Participants viewed alternating photographs of their spouse and a familiar, neutral acquaintance while undergoing fMRI. At the start of each viewing block they were asked to recall non-sexual shared memories related to the person shown, and they rated their mood during the session to confirm that the images evoked the intended emotional responses. Saliva samples were also collected to test polymorphisms in genes associated with pair-bonding and social behavior, including AVPR1a (vasopressin receptor), OXTR (oxytocin receptor), COMT (a dopamine-related enzyme), and the DRD4-7R dopamine receptor variant.
The results highlighted a central role for dopamine-rich brain regions in the maintenance of romantic love. Activity in the substantia nigra and ventral tegmental area—key nodes of the brain’s reward and motivation system—correlated with measures of romantic love across both time points. These regions are strongly linked to motivation, reward-seeking, energy, and feelings such as excitement and euphoria, which align with common descriptions of romantic attraction and commitment.
Genetic interactions amplified these neural responses. Variations in vasopressin, oxytocin, and dopamine-related genes were associated with stronger activation in the ventral tegmental area and related reward circuitry. These findings mirror research in monogamous mammals and suggest that human pair-bonding draws on evolutionarily conserved neurochemical systems.
Beyond core reward centers, romantic love maintenance also related to activity in cortical regions involved in sensory processing, attention, and social cognition. The paracentral lobule, a region tied to genital sensory representation, showed links with measures of sustained romantic love, echoing the role of sexual intimacy in strengthening long-term relationships. Occipital, insular, and angular gyrus activations point to how sensory, emotional, and cognitive systems collaborate to support attachment and partner-focused bonding over time.
Acevedo emphasizes that while brain chemistry and genetics shape the capacity to form and sustain romantic bonds, they are only part of the story. Human relationships are constructed through everyday behaviors, shared experiences, and deliberate efforts to care for a partner. “Romantic love inspires people to learn what makes their partner smile,” she notes. “Those gestures—small acts of kindness, attention to a partner’s happiness—reinforce reward systems in the brain and help keep relationships stable.”
The study builds on Acevedo’s prior work on empathy and altruism, showing that although humans can experience prosocial feelings toward strangers, neural responses are often strongest for close partners. In healthy relationships, romantic love commonly includes empathic and altruistic dimensions, but romantic attachment can be distinct in its neural signature.
Some readers may find it reductive to explain love in terms of genes and neural activity. Acevedo cautions against viewing biology as destiny: genetic predispositions and brain responses create tendencies, not inevitabilities. Human creativity, culture, and everyday choices remain essential in maintaining intimacy. The reward activation linked to seeing a smiling partner or learning that something good has happened to them demonstrates how reciprocal care and shared joy reinforce attachment in lived relationships.
In sum, this research suggests that romantic love maintenance reflects a complex interplay between evolutionarily conserved reward mechanisms, higher-order cognitive processing, and genetic differences in neurochemical systems. These findings support the idea that sustaining romantic bonds is part of a broader mammalian strategy for mating and long-term attachment, shaped by both biology and behavior.
About this neuroscience research article
Source: UC Santa Barbara
Media contacts: Jim Logan – UC Santa Barbara
Image source: The image is in the public domain.
Original Research: Open access. Title cited by the authors: “After the Honeymoon: Neural and Genetic Correlates of Romantic Love in Newlywed Marriages” by Bianca P. Acevedo et al., published in Frontiers in Psychology.
Abstract (summary)
The study examined the neural and genetic correlates of romantic love maintenance in 19 first-time newlyweds using fMRI and genetic testing. Participants viewed partner and acquaintance faces at two time points—around the wedding and one year later—and provided saliva samples to genotype AVPR1a, OXTR, COMT, and DRD4-7R polymorphisms. Findings linked sustained romantic love to activation in dopamine-rich regions (substantia nigra and ventral tegmental area) and to interactions with vasopressin, oxytocin, and dopamine-related genes. Additional correlations appeared in somatosensory and cortical areas tied to sexual and cognitive processing. The results suggest that romantic love maintenance is supported by dopamine-, vasopressin-, and oxytocin-related brain systems and influenced by genetic variation, reflecting a mammalian strategy for reproduction and long-term attachment.
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