Autism in Young Children:Restricted/Repetitive Behaviors

限制和重复的行为和兴趣（RRB）是自闭症的一个定义特征。虽然这组行为对临床诊断至关重要，但相对于自闭症的社交和沟通问题，这组行为的研究却少得可怜。具体而言，对RRB的发展、进程和独特性的理解有限。该项目的目的是检查患有自闭症或自闭症谱系障碍（ASD）的幼儿（2岁和3岁）的RRB。RRB包括一系列不同的行为，如重复的运动动作、仪式、惯例和强迫。RRB的存在和质量已被证明会对适应和社会功能产生不利影响，并预测自闭症症状的严重程度。 描述RRB的发展过程将允许检查其对自闭症的社会和沟通结果的直接影响。这与个体化治疗以及基于症状群构建亚组直接相关。先前对自闭症RRB的研究研究了老年人或有严重认知障碍的人，但没有研究患有自闭症和一系列认知功能的幼儿。然而，从对患有发育障碍的幼儿（如唐氏综合征）的研究中可以清楚地看到，RRB出现得更早，应该在2至3岁的年龄段进行调查。本研究将阐明自闭症与典型发育和发育障碍的RRB的发展方面。 这项比较性的纵向研究将记录RRB的早期发展以及这些行为在三组幼儿中的差异：1）2至3岁的自闭症/ASD儿童; 2）2至3岁的发育障碍儿童（DD）; 3）典型发育儿童（TD）。DD和TD组将根据心理年龄与自闭症/ASD组相匹配。所有儿童都将接受一系列全面的评估，以评估RRB的发生率，频率和强度以及社交，沟通和行为功能。这是第一项使用多种方法（直接）检查自闭症或ASD幼儿RRB的研究。 观察和举报人报告）。本研究将（1）记录自闭症儿童与非自闭症儿童的RRB的过程和发展轨迹;（2）检查RRB与自闭症儿童社会交往结果的关系;（3）基于共现、随时间的模式，构建可能构成自闭症中重要亚型的RRB分组，和强度，以及（4）使用RRB作为该数据集中表型分层的基础，以鉴定与RRB和/或自闭症相关的基因。

Restricted and repetitive behaviors and interests (RRBs) are a defining characteristic of autism. While essential to clinical diagnosis, this group of behaviors is woefully understudied relative to social and communication problems in autism. Specifically, there is limited understanding of the development, course, and uniqueness of RRBs. The objective of this project is to examine RRBs in young children (ages 2 and 3 years of age) with autism or autism spectrum disorder (ASD). RRBs comprise a diverse set of behaviors such as repetitive motor actions, rituals, routines, and compulsions. The presence and quality of RRBs have been shown to adversely affect both adaptive and social functioning and also predict severity of autism symptoms. Characterizing the developmental course of RRBs will allow for examination of their direct impact on social and communication outcomes in autism. This is directly relevant to individualizing treatment as well as constructing subgroups based on clusters of symptoms. Prior investigations of RRBs in autism have studied older individuals or those with severe cognitive impairments, but not young children with autism and a range of cognitive functioning. However, it is clear from studies of young children with developmental disabilities such as Down syndrome that RRBs emerge much earlier and should be investigated in this 2- to 3-year old age period. This study will elucidate the developmental aspects of RRBs in autism versus typical development and developmental disabilities. This comparative, longitudinal study will document the early development of RRBs and how these behaviors differ in three groups of young children: 1) children with autism/ASD between 2 and 3 years of age; 2) children with developmental disabilities (DD) between 2 and 3 years of age, and 3) typically developing children (TD). Both DD and TD groups will be matched to the autism/ASD groups on the basis of mental age. All children will be serially evaluated with a comprehensive battery of measures to assess the occurrence, frequency, and intensity of RRBs as well as social, communicative, and behavioral functioning. This is the first study to examine RRBs in young children with autism or ASD using multiple methods (direct observation and informant report). The current study will (1) document the course and developmental trajectory of RRBs in young children with autism vs. non-autism; (2) examine the relationship of RRBs to social-communicative outcomes in autism; (3) construct groupings of RRBs that may constitute significant subtypes in autism based on co-occurrence, patterns over time, and intensity and (4) use RRBs as the basis for phenotypic stratification in this data set to identify genes associated with RRBs and/or autism.