Neural evidence for long-term marriage shaping the functional brain network organization between couples

Long-term married couples have been reported to share personality and behavioural similarities, but whether long-term marriage would shape the brain is hitherto unknown. In this study, 35 pairs of long-term married couples, who have married and living together at least 30 years, were recruited, and resting state functional magnetic resonance imaging was used to examine the neural correlates of long-term marriage between couples. Seven intrinsic connectivity networks were extracted using spatially constrained group independent component analysis, and the spatial similarity of each network as well as functional connectome similarity between couples were investigated respectively. The significant spatial similarities in the salience and frontoparietal networks as well as marginally significant connectome similarity were observed in long-term married couples. In addition, the marital duration showed a significantly positive correlation with the spatial similarity in the frontoparietal network and connectome similarity. The results provide objective evidence that long-term marriage would shape brain network organization, and the combination of initial personality traits and long-term common experience of the couples may be potential factors that account for similar brain network organizations between couples.