Understanding others is fundamental to interpersonal coordination and successful cooperation. One mechanism posited to underlie both effective communication and behavioral coordination is interpersonal neural synchrony. Although presumably foundational for children's social development, research on neural synchrony in naturalistic caregiver-child interactions is lacking. Using dual-functional near-infrared spectroscopy (fNIRS), we examined the effects of interaction quality on neural synchrony during a problem-solving task in 42 dyads of mothers and their preschool children. In a cooperation condition, mothers and children were instructed to solve a tangram puzzle together. In an individual condition, mothers and children performed the same task alone with an opaque screen between them. Wavelet transform coherence (WTC) was used to assess the cross-correlation between the two fNIRS time series. Results revealed increased neural synchrony in bilateral prefrontal cortex and temporo-parietal areas during cooperative as compared to individual problem solving. Higher neural synchrony during cooperation correlated with higher behavioral reciprocity and neural synchrony predicted the dyad's problem-solving success beyond reciprocal behavior between mothers and children. State-like factors, such as maternal stress and child agency during the task, played a bigger role for neural synchronization than trait-like factors, such as child temperament. Our results emphasize neural synchrony as a biomarker for mother-child interaction quality. These findings further highlight the role of state-like factors in interpersonal synchronization processes linked to successful coordination with others and in the long-term might improve the understanding of others.

中文翻译：

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母子问题解决过程中交互质量对神经同步性的影响。

理解他人是人际协调和成功合作的基础。人际神经同步是建立有效沟通和行为协调基础的一种机制。尽管大概是儿童社会发展的基础，但缺乏对自然主义的照顾者-儿童互动中的神经同步性的研究。使用双功能近红外光谱法（fNIRS），我们在42位母亲及其学龄前儿童中，在解决问题的过程中检查了交互质量对神经同步性的影响。在合作条件下，母亲和孩子被指示一起解决七巧板难题。在个别情况下，母亲和孩子单独执行相同的任务，并且屏幕之间不透明。小波变换相干性（WTC）用于评估两个fNIRS时间序列之间的互相关。结果显示，与个体问题解决相比，合作过程中双侧前额叶皮层和颞顶叶区域的神经同步性增加。合作过程中较高的神经同步性与较高的行为互惠性相关，并且神经同步性预测了二元组解决问题的成功超越了母子之间的相互行为。在任务执行过程中，诸如母亲压力和儿童活动能力之类的状态性因素对神经同步的作用要比诸如儿童气质之类的性状特征因素起更​​大的作用。我们的研究结果强调神经同步是母子互动质量的生物标志。