Center for Neurodevelopment and Imaging Research, Kennedy Krieger Institute, Baltimore, Maryland; School of Psychology, University of Nottingham, Nottingham, United Kingdom.
Mathematical Institute for Data Science, Johns Hopkins University, Baltimore, Maryland; Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland.
Biol Psychiatry Cogn Neurosci Neuroimaging. 2021 Mar;6(3):321-328. doi: 10.1016/j.bpsc.2020.09.001. Epub 2020 Sep 10.
Imitation deficits are prevalent in autism spectrum conditions (ASCs) and are associated with core autistic traits. Imitating others' actions is central to the development of social skills in typically developing populations, as it facilitates social learning and bond formation. We present a Computerized Assessment of Motor Imitation (CAMI) using a brief (1-min), highly engaging video game task.
Using Kinect Xbox motion tracking technology, we recorded 48 children (27 with ASCs, 21 typically developing) as they imitated a model's dance movements. We implemented an algorithm based on metric learning and dynamic time warping that automatically detects and evaluates the important joints and returns a score considering spatial position and timing differences between the child and the model. To establish construct validity and reliability, we compared imitation performance measured by the CAMI method to the more traditional human observation coding (HOC) method across repeated trials and two different movement sequences.
Results revealed poorer imitation in children with ASCs than in typically developing children (ps < .005), with poorer imitation being associated with increased core autism symptoms. While strong correlations between the CAMI and HOC methods (rs = .69-.87) confirmed the CAMI's construct validity, CAMI scores classified the children into diagnostic groups better than the HOC scores (accuracy = 87.2%, accuracy = 74.4%). Finally, by comparing repeated movement trials, we demonstrated high test-retest reliability of CAMI (rs = .73-.86).
Findings support the CAMI as an objective, highly scalable, directly interpretable method for assessing motor imitation differences, providing a promising biomarker for defining biologically meaningful ASC subtypes and guiding intervention.
模仿缺陷在自闭症谱系障碍(ASD)中很常见,与核心自闭症特征有关。模仿他人的动作对于典型发展人群的社交技能发展至关重要,因为它促进了社会学习和纽带的形成。我们提出了一种使用简短(1 分钟)、高度吸引人的视频游戏任务的计算机化运动模仿评估(CAMI)。
我们使用 Kinect Xbox 运动跟踪技术,记录了 48 名儿童(27 名患有 ASD,21 名发育正常)模仿模型舞蹈动作的情况。我们实现了一种基于度量学习和动态时间规整的算法,该算法自动检测和评估重要关节,并根据儿童和模型之间的空间位置和时间差异返回分数。为了建立构念效度和可靠性,我们比较了 CAMI 方法测量的模仿性能与更传统的人类观察编码(HOC)方法在重复试验和两种不同运动序列中的表现。
结果表明,ASD 儿童的模仿能力比发育正常儿童差(p <.005),模仿能力差与核心自闭症症状增加有关。CAMI 与 HOC 方法之间的强相关性(rs =.69-.87)证实了 CAMI 的构念效度,CAMI 评分比 HOC 评分更好地将儿童分类为诊断组(准确率=87.2%,准确率=74.4%)。最后,通过比较重复运动试验,我们证明了 CAMI 的高测试-重测信度(rs =.73-.86)。
研究结果支持 CAMI 作为一种客观、高度可扩展、可直接解释的评估运动模仿差异的方法,为定义具有生物学意义的 ASC 亚型和指导干预提供了有前途的生物标志物。