Department of Psychology and Gonda Brain Sciences Center, Bar-Ilan University, Ramat-Gan, Israel.
Neuropsychopharmacology. 2011 Dec;36(13):2603-15. doi: 10.1038/npp.2011.172. Epub 2011 Aug 31.
The mother-infant bond provides the foundation for the infant's future mental health and adaptation and depends on the provision of species-typical maternal behaviors that are supported by neuroendocrine and motivation-affective neural systems. Animal research has demonstrated that natural variations in patterns of maternal care chart discrete profiles of maternal brain-behavior relationships that uniquely shape the infant's lifetime capacities for stress regulation and social affiliation. Such patterns of maternal care are mediated by the neuropeptide Oxytocin and by stress- and reward-related neural systems. Human studies have similarly shown that maternal synchrony--the coordination of maternal behavior with infant signals--and intrusiveness--the excessive expression of maternal behavior--describe distinct and stable maternal styles that bear long-term consequences for infant well-being. To integrate brain, hormones, and behavior in the study of maternal-infant bonding, we examined the fMRI responses of synchronous vs intrusive mothers to dynamic, ecologically valid infant videos and their correlations with plasma Oxytocin. In all, 23 mothers were videotaped at home interacting with their infants and plasma OT assayed. Sessions were micro-coded for synchrony and intrusiveness. Mothers were scanned while observing several own and standard infant-related vignettes. Synchronous mothers showed greater activations in the left nucleus accumbens (NAcc) and intrusive mothers exhibited higher activations in the right amygdala. Functional connectivity analysis revealed that among synchronous mothers, left NAcc and right amygdala were functionally correlated with emotion modulation, theory-of-mind, and empathy networks. Among intrusive mothers, left NAcc and right amygdala were functionally correlated with pro-action areas. Sorting points into neighborhood (SPIN) analysis demonstrated that in the synchronous group, left NAcc and right amygdala activations showed clearer organization across time, whereas among intrusive mothers, activations of these nuclei exhibited greater cross-time disorganization. Correlations between Oxytocin with left NAcc and right amygdala activations were found only in the synchronous group. Well-adapted parenting appears to be underlay by reward-related motivational mechanisms, temporal organization, and affiliation hormones, whereas anxious parenting is likely mediated by stress-related mechanisms and greater neural disorganization. Assessing the integration of motivation and social networks into unified neural activity that reflects variations in patterns of parental care may prove useful for the study of optimal vs high-risk parenting.
母婴纽带为婴儿未来的心理健康和适应能力奠定基础，取决于提供物种典型的母婴行为，这些行为得到神经内分泌和动机情感神经系统的支持。动物研究表明，母婴护理模式的自然变化描绘了独特的母婴大脑行为关系图谱，这些图谱独特地塑造了婴儿一生的压力调节和社交联系能力。这种母婴护理模式是由神经肽催产素和与应激和奖励相关的神经系统介导的。人类研究也表明，母婴同步——母婴行为与婴儿信号的协调——和过度表达——母婴行为的过度表达——描述了独特而稳定的母婴风格，对婴儿的幸福有着长期的影响。为了将大脑、激素和行为整合到母婴纽带的研究中，我们检查了同步和过度表达的母亲对动态、生态有效的婴儿视频的 fMRI 反应及其与血浆催产素的相关性。共有 23 名母亲在家中与婴儿互动时被录像，并对其血浆 OT 进行了检测。会议按同步性和过度表达性进行微编码。母亲在观察几个自己和标准婴儿相关的小插曲时进行扫描。同步母亲的左伏隔核（NAcc）活跃度更高，过度表达的母亲的右杏仁核活跃度更高。功能连接分析显示，在同步母亲中，左 NAcc 和右杏仁核与情绪调节、心理理论和同理心网络功能相关。在过度表达的母亲中，左 NAcc 和右杏仁核与前动区功能相关。分类点到邻域（SPIN）分析表明，在同步组中，左 NAcc 和右杏仁核的激活在时间上表现出更清晰的组织，而在过度表达的母亲中，这些核的激活表现出更大的跨时间不组织。只有在同步组中才发现催产素与左 NAcc 和右杏仁核激活之间的相关性。适应性强的育儿方式似乎是由奖励相关的动机机制、时间组织和关联激素所支撑的，而焦虑型育儿方式可能是由应激相关机制和更大的神经紊乱所介导的。评估动机和社交网络的整合到反映父母照顾模式变化的统一神经活动中，可能对最佳与高风险育儿的研究有用。
