本项目拟以前国自然项目(31470994)为基础，继续追踪2015队列数据库儿童在5、6、7岁三个年龄点的问题行为，在RDoC框架下，从问题行为的发生、轨迹形成及过程机制三方面动态考察“儿童早期问题行为发展轨迹及因果机制”。采用交叉滞后准实验设计，利用行为实验与编码、问卷评估、临床诊断、fNIRS及唾液皮质醇分析等多种方法和技术，系统考察：1）儿童7年外化和内化问题发展轨迹，验证冲动和焦虑可能分别是外化和内化问题发生的根源; 2）揭示母子互动中神经同步与行为同步先后顺序的年龄特点，及通过执行功能影响问题行为的因果机制，区分母子互动与压力任务中的同步性的不同作用；3）探讨执行功能、多水平母子互动同步性与问题行为的中介过程。期望该研究从更新的角度完善Beauchaine等的外化问题模型及双因素模型；丰富发展心理病理学交互作用理论，为精神疾病分类和治疗提供新工具，为未来诊断分类的修订提供依据。

Early childhood behavior problems occur in as many as 15% of young children and are the most common referral reason at mental health clinics serving young children (Bagner et al, 2015). In our previous studies (Beijing Cohort 2015), which were supported by NSFC (NO. 31470994), 244 infants have participated in 4 waves of data collection since they were 6 months of age with their parents. Children’s behavior problems were reported by their caregivers when they were 1 year, 2 years and 3 years old. Based on this work, the present project will continue the longitudinal data collections of children’s behavior problems during the transition from preschool to school-age. According to the RDoC framework, the trajectories of behavior problems during early childhood and the casual mechanism will be discussed in this project, including the origin, development trajectory and the development processes of behavior problems. A quasi-experimental design, cross-lagged approach, will be adopted. Multiple ways of measurement will be used, including behavior observation and coding, experiment tasks in the laboratory, questionnaires, clinical diagnosis, fNIRS and salivary cortisol analysis, to achieve three main goals. First of all, to capture and characterize the developmental trajectories of externalizing and internalizing behavior problems from 1 to 7 years old; then the hypothesis that impulsive and anxious traits might be the origins of externalizing and internalizing behavior problems will be verified. Secondly, to clear the sequence and the age-related change of neural and behavioral synchrony during child-mother interaction; and to distinguish the different roles of these synchronies between nature interaction and stressful situation. Finally, to understanding how (a)synchrony of child-mother interaction in behavioral, physiological and neural levels influence behavior problems through children’s executive functions. It is expected that the findings of this project will a) expand Beauchaine and McNulty (2013)’s developmental spectrum model of externalizing behavior problems; b) test the bifactor model of externalizing and internalizing problems; c) enrich and refine the interaction theory of developmental psychopathology and provide evidence for clinical diagnosis psychopathology of children and measurements.