Temporal changes in functional magnetic resonance imaging activation of heterosexual couples for visual stimuli of loved partners

Objective: Previous neuroimaging studies on romantic love have focused on determining how the visual stimuli that serve as a representation of loved ones induce the neural activation patterns of romantic love. The purpose of this study was to investigate the temporal changes in romantic love over a period of 6 months and their correlated neurophysiological changes. Methods: Five heterosexual couples (n=10, mean age 21.1±1.97) who started dating not less than 100 days previously were recruited to measure their blood oxygen level dependent (BOLD) signals using functional magnetic resonance imaging (fMRI) while showing them pictures of their loved ones and their previously identified, opposite-sex friends. Subsequently, the subjects were scanned under the same experimental conditions to assess possible changes in their brain activities after 180 days. Results: We found that their Passionate Love Score (PLS) values (M: 118.6±9.1, F: 120.2 ±7.0) were significantly reduced after 6 months (M: 110.8±4.0, F: 106.2±3.0). Furthermore, significantly increased activations were found in the cingulate gyri, inferior frontal gyri, supramarginal gyri, etc., after 6 months, whereas the head and tail of the right caudate nucleus were deactivated, which is indicative of the inhibition of expression and sengory neglect. Conclusion: These findings suggest that dynamic neural processes in the cortical-subcortical regions are involved in temporal changes in romantic love.