良好的婚姻是个人幸福、家庭和睦，乃至社会和谐的重要源泉。而新婚阶段又是整个家庭生命周期中最复杂、最充满挑战的时期。夫妻之间的相似性是婚姻关系中最为基础的成分，对婚姻关系及其走向具有重要作用。关于夫妻相似性对关系质量的影响作用方向，存在两个对立的假说：认为相似性对关系质量具有积极作用的相似性假说，以及认为相似性对关系质量具有消极作用的互补假说。已有研究更多从行为层面验证并阐释了夫妻在某些特征上的相似性对婚姻质量的积极影响，但仍有部分研究支持了互补假说。这提示我们不同方面的相似性对婚姻质量的影响作用可能是不同的，仅仅强调夫妻相似性对婚姻质量的积极作用是不全面和有偏的。只关注有限几个行为特质的相似性还会受到测量工具和测量方式等因素的影响，限制了结果的全面性和可靠性。因此，本研究从认知神经层面考察了新婚夫妻相似性对婚姻质量的影响，尝试构建一个动态整合的理论模型，将夫妻相似性对婚姻质量的积极和消极作用整合起来进行阐述，并结合动态变化视角，更全面、发展地理解夫妻相似性对婚姻质量的影响作用及其神经机制。基于此，本研究进行了两项追踪研究，聚焦新婚夫妻在自然观看社会情绪刺激时的大脑功能连接相似性这一客观、综合的相似性指标，采用基于连接组的预测模型（Connectome-based predictive modeling），全面、动态地考察新婚夫妻相似性对婚姻质量的影响作用，揭示夫妻相似性影响婚姻质量的神经指标，解析其影响婚姻质量的具体机制。   
研究一探讨了新婚夫妻相似性对婚姻质量的影响及影响机制。研究采用功能性磁共振成像技术（functional magnetic resonance imaging, fMRI）采集了29对新婚夫妻分别观看中国情绪影像材料库中愉快、中性、悲伤和愤怒的情绪视频时的功能连接并计算夫妻间的相似性，观看配偶的积极（赞赏和理解）和消极（批评和控制）互动行为视频（模拟互动情境）时的脑反应，以及在扫描时和13个月后报告的婚姻质量。结果发现：（1）基于新婚夫妻功能连接相似性的预测模型可以显著预测妻子当前的婚姻质量，具体而言，颞叶与前额叶之间、颞叶与顶叶之间、颞叶与小脑之间的功能连接的相似性与妻子的婚姻质量呈正相关（本文中称它为正性功能连接相似性指标）；而小脑与皮层下区域之间、小脑与前额叶之间、小脑与运动区之间的功能连接的相似性与妻子的婚姻质量呈负相关（本文中称它为负性功能连接相似性指标）；（2）预测妻子当前婚姻质量的功能连接相似性指标还可以边缘显著地通过妻子加工配偶积极互动行为时右侧背外侧前额叶的反应影响13个月后妻子和丈夫的婚姻质量。这些结果表明功能连接相似性对妻子当前的婚姻质量同时存在积极和消极作用，与观点采择和人际理解有关的功能连接的相似性对妻子的婚姻质量具有积极作用，而与神经质、不安全依恋和消极情绪有关的功能连接的相似性对妻子的婚姻质量具有消极作用。此外，夫妻相似性还可以通过妻子在积极互动中的情绪控制对妻子和丈夫的婚姻质量产生长时影响。
研究二进一步从发展变化的角度探究了新婚夫妻相似性变化对婚姻质量变化的影响和影响机制。研究采用功能性近红外光学成像技术（functional near-infrared spectroscopy, fNIRS）采集了夫妻分别观看包含观点争议和冲突事件的视频刺激时的功能连接相似性，在自然互动（积极的愉快话题讨论和消极的冲突话题讨论）时的脑间活动同步，以及他们主观报告的婚姻质量。八十二对结婚一年内的新婚夫妻完成了第一次测查，截至论文撰写时，34对夫妻完成了半年后的追踪测查。结果发现：（1）T1时，夫妻在初级躯体感觉皮层内部、额上回与角回之间、额极与颞极之间的功能连接的相似性可以显著正向预测T1妻子的婚姻质量（正性功能连接相似性指标）；而T2时，夫妻在视觉区内部、顶下小叶内部、角回与额下回之间、角回与楔前叶之间的功能连接的相似性可以显著负向预测T2妻子的婚姻质量（负性功能连接相似性指标）。（2）夫妻的正性功能连接相似性指标在6个月后表现出增加趋势，但并未显著高于随机水平；而夫妻的负性功能连接相似性指标在6个月后的下降幅度显著大于随机水平。（3）正性功能连接相似性指标的变化可以显著正向预测妻子婚姻质量的变化，而负性功能连接相似性指标的变化则通过夫妻在积极互动时的脑间活动同步（妻子左侧颞中回到4s后丈夫右侧背外侧前额叶）的变化进而边缘显著地负向预测妻子婚姻质量的变化。研究二表明：在婚姻早期，与情绪调节和行为理解相关的功能连接的相似性可以促进妻子的婚姻质量；而随着婚龄的增长，与神经质、自我关注（self-focus）和消极情绪相关的功能连接的相似性会损害妻子的婚姻质量。对婚姻质量有积极影响的功能连接相似性的增加可以直接促进婚姻质量的上升，而对婚姻质量有消极影响的功能连接相似性的增加则会通过损害夫妻积极互动间接引起婚姻质量的下降。
总之，本研究发现相较于丈夫，新婚夫妻相似性对妻子的婚姻质量具有更大的影响作用，并且同时包含积极作用和消极作用：与观点采择、人际理解和情绪调节等有关的功能连接的相似性对婚姻质量具有积极作用，而与神经质、自我关注和消极情绪等有关的功能连接的相似性会对婚姻质量产生消极影响。积极和消极作用的相对大小会随着婚龄改变：在婚姻早期（如：结婚一年内），观点共识和相互理解对婚姻质量的积极作用更为突出；而随着婚龄的增长，相似程度的自我关注和消极情绪则对婚姻质量产生更显著的消极影响。夫妻相似性对婚姻质量产生积极和消极影响的作用模式不同，并且夫妻积极互动主要在相似性对婚姻质量产生消极影响的过程中发挥中介作用。本研究整合了相似性假说、互补假说和易感性-压力-婚姻调适模型，并增加动态发展的视角，尝试构建了夫妻相似性影响婚姻质量的动态整合模型，全面阐释夫妻相似性对婚姻质量的影响及影响机制；同时揭示新婚夫妻相似性影响婚姻质量的神经指标，进一步明确相似性假说和互补假说的主要适用领域，为发展有效的临床和神经干预方案提供了借鉴。

A good marriage is an important source of personal happiness, domestic peace, and even social harmony, and the newlywed phase is the most complex and challenging time in the family's life cycle. Conjugal similarity is the most basic component of marriage and plays a crucial role in marital quality. There are two opposing hypotheses about the effect of conjugal similarity on relationship quality: the similarity hypothesis that assumes similarity has a positive effect on relationship quality, and the complementary hypothesis that contends similarity has a negative effect on relationship quality. Most studies have mainly verified and explained the positive impact of similarity in certain characteristics on marital quality from the behavioral level, but some studies still support the complementary hypothesis. This may suggest that similarities in different aspects may have different effects on marital quality, and only emphasizing the positive effect may be incomplete and biased. Besides, focusing on similarity in limited behavior characteristics would be affected by measurement tools and measurement methods, and this would limit the comprehensiveness and reliability of the results. Therefore, the current study attempted to examine the influence of conjugal similarity on marital quality among newlyweds from the neurocognitive level, and built a dynamic integrated theoretical model, integrating the positive and negative effect of conjugal similarity on marital quality, combining the dynamic change perspective, to comprehensively and developmentally understand the effect of conjugal similarity on the marital quality. Thus, current study conducted two longitudinal studies, focusing on the brain functional connectivity similarity in newlyweds during processing of social-emotion stimuli, an objective and comprehensive similarity measurement, using connectome-based predictive modeling (CPM) to comprehensively and dynamically investigate the effect of conjugal similarity on marital quality in newlyweds, reveal the neural indicators of the influence of conjugal similarity on marital quality, and analyze the mechanism of its impact on marital quality.
The study 1 explored the influence and mechanism of conjugal similarity on marital quality. Functional magnetic resonance imaging (fMRI) data of 29 newlyweds when they watched happy, neutral, sad and angry emotional videos of the Chinese affective video system (functional connectivity similarity), and watched videos of spousal positive (appreciation and understanding) and negative (criticization and dominance) interactive behaviors (neural responses during marital interaction), as well as marital quality at scanning and 13 months later were collected. The results showed that (1) The similarity in functional connectivity responding to emotional videos significantly predicted the current marital quality of wife. Specifically, the similarity in functional connectivity between temporal lobe and prefrontal lobe, between temporal lobe and parietal lobe, and between temporal lobe and cerebellum are positively related to wife’ marital quality (positive functional connectivity similarity index); the similarity in functional connectivity between cerebellum and subcortical regions, between cerebellum and prefrontal lobe, and between cerebellum and motor areas are negatively related to wife’ marital quality (negative functional connectivity similarity index). (2) the functional connectivity similarity index could marginally significantly affect the wife’s and husband’s marital quality after 13 months via wife’s right dorsolateral prefrontal activity to their spousal positive interactive behaviors. These results suggested that functional connectivity similarity had not only positive but also negative effects on wife’s current marital quality. Similarity in functional connectivity related to perspective-taking, interpersonal understanding had a positive impact on wife’s marital quality, while similarity in functional connectivity related to neuroticism and negative emotion had a negative impact on wife’s marital quality. They could also show long-term effects on wife’s and husband’s marital quality via wife’s emotional control during positive interactions.
The study 2 further explored the impact and influence mechanism of newlyweds' change in functional connectivity similarity on change in marriage quality, from the perspective of development and change. Eighty-two newlyweds married within one year completed the first survey, and by the time of this paper, 34 couples completed the follow-up study 6 months later. Functional near-infrared spectroscopy (fNIRS) data during processing videos containing controversial and conflicting events (functional connectivity similarity), and during natural interactions including positive discussion of pleasant topic and negative discussion of conflict topic (interpersonal neural synchronization (INS)), and the marital quality were collected. The results showed that: (1) At T1, the similarity in functional connectivity between primary somatosensory cortex, between superior frontal gyrus and angular gyrus, and between frontal pole and temporal pole significantly positively predicted wife’s current (T1) marital quality; while at T2, the similarity in functional connectivity within the visual area, within the inferior parietal lobe, between the angular gyrus and the inferior frontal gyrus, and between the angular gyrus and the precuneus significantly negatively predicted wife’s current (T2) marital quality. (2) The positive functional connectivity similarity index increased after 6 months, but the increase was not significantly higher than the random level; while, the negative functional connectivity similarity index decreased significantly more than the random level after 6 months. (3) The change in positive functional connectivity similarity index positively influenced the change of wife’s marital quality directly, while the change in negative functional connectivity similarity index indirectly negatively (marginally significantly) influenced the change of wife’s marital quality via the change in INS (wife’s left middle temporal gyrus - husband’s dorsolateral prefrontal lagged by 4 s) during couple’s positive interaction. Study 2 showed that in the early stage of marriage, the similarity in functional connectivity related to perspective-taking, behavioral understanding and emotional regulation had positive effect on wife’s marital quality, while as the marriage duration grows, the similarity in functional connectivity related to neuroticism, self-focus and negative emotion had negative effect on the wife’s marital quality. The increase of functional connectivity similarity which has a positive effect on marital quality can directly promote the improvement of marital quality, while the increase of functional connectivity similarity which has a negative effect on marital quality indirectly cause the decrease of marital quality through damaging positive marital interaction.
In conclusion, this study showed that compared with husband’s marital quality, conjugal similarity had a greater impact on wife’s marital quality among newlyweds, including both positive and negative effects. The similarity in functional connectivity related to perspective-taking, interpersonal understanding and emotional regulation promote marital quality, while the similarity in functional connectivity related to neuroticism, self-focus and negative emotion can damage the relationship. The relative magnitude of positive and negative effects will change with the marriage duration: shared views and mutual understanding has a more prominent positive effect on wife’s marital quality, while as the marriage duration grows, the similar levels of self-focus and negative emotions has a more significant negative effect on the wife’s marital quality. The functional connectivity similarity index with positive and negative effects showed different influence patterns on the wife's marital quality, and the positive marital interaction mainly plays a mediating role in the negative effect of conjugal similarity on marital quality. The current study, integrating the similarity hypothesis, complementarity hypothesis and vulnerability-stress-adaptation model, and combining the dynamic and developmental perspective, constructed a dynamic integrated model of the impact of similarity on marital quality, which comprehensively explained the effect and the influence mechanism of conjugal similarity on marital quality from the neural level, revealed the neural indicator, further clarified the main application fields of similarity hypothesis and complementary hypothesis, and provided a reference for the development of effective clinical and neurological interventions.