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Altered brain network organization in romantic love as measured with resting-state fMRI and graph theory

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Abstract

Romantic love is a complex state that has been seen as similar to addiction. Previous task-based functional magnetic resonance imaging (fMRI) studies have shown that being in love is closely associated with functional brain changes in the reward and motivation system. However, romantic love-related functional connectivity network organization in resting-state fMRI has yet to be elucidated. To that end, here we used resting-state fMRI and graph theory to compare whole-brain functional network topology between an “in-love” group (n = 34, 16 females, currently in love and in a romantic relationship) and a “single” group (n = 32, 14 females, never in love and not in a romantic relationship). Compared to the single group, we found lower network segregation in the love group (i.e., lower small-worldness, mean clustering coefficient, and modularity), and these metrics were negatively associated with scores on the Passionate Love Scale (PLS) (an index of intense passionate/romantic love). Additionally, the love group displayed altered connectivity degree (reflecting the importance of a node): decreased degree in left angular gyrus and left medial orbitofrontal cortex, but increased degree in left fusiform gyrus. Furthermore, local efficiency or degree of these regions was significantly correlated to PLS scores. Taken together, results showed decreased overall brain functional segregation but enhanced emotional-social processing in romantic lovers. These findings provide the first evidence of love-related brain network organization changes and suggest similar but different brain network alterations between romantic love and addiction, providing new insights on the neural systems underlying romantic love.

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Acknowledgements

We thank Yun Tian for his help in data processing.

Funding sources

This study was funded by the Fundamental Research Funds for the Central Universities (#SWU1809006) and the National Natural Science Foundation of China (31771237).

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  1. Chuan Wang and Sensen Song contributed equally to this work and share first authorship.

Authors and Affiliations

  1. Faculty of Psychology, Southwest University, Chongqing, 400715, China

    Chuan Wang, Hong Chen & Zhiling Zou

  2. Department of Psychology, School of Humanities, Tongji University, Shanghai, 200092, China

    Sensen Song

  3. Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02114, USA

    Federico d’Oleire Uquillas

  4. Department of Psychiatry, University of Minnesota, Minneapolis, MN, 55414, USA

    Anna Zilverstand

  5. School of Humanities and Social Science, University of Science and Technology of China, Hefei, 230026, China

    Hongwen Song

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  1. Chuan Wang
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Contributions

Z.Z., and H.C. were responsible for the original study design. C.W., S.S. and H.S. collected the data. C.W. and F.d.U. performed data analysis. Z.Z., C.W., A.Z., and H.C. interpreted the findings. C.W., S.S. and F.d.U. wrote the manuscript. All authors contributed to the final version, approved the publication of the final version and agreed to be accountable for the integrity and accuracy of all aspects of the work.

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Correspondence to Hong Chen or Zhiling Zou.

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This study was approved by the Ethics Committee of Southwest University (Chongqing, China). Informed consent was obtained from all individual participants included in the study.

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Wang, C., Song, S., d’Oleire Uquillas, F. et al. Altered brain network organization in romantic love as measured with resting-state fMRI and graph theory. Brain Imaging and Behavior 14, 2771–2784 (2020). https://doi.org/10.1007/s11682-019-00226-0

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