Background: Motor dysfunction has been reported as one of the first signs of atypical development in infants at high familial risk for autism spectrum disorder (ASD) (HR infants). However, studies have shown inconsistent results regarding the nature of motor dysfunction and whether it can be predictive of later ASD diagnosis. This is likely because current standardized motor assessments may not identify subtle and specific motor impairments that precede clinically observable motor dysfunction. Quantitative measures of motor development may address these limitations by providing objective evaluation of subtle motor differences in infancy. Methods: We used Opal wearable sensors to longitudinally evaluate full day motor activity in HR infants, and develop a measure of motion complexity. We focus on complexity of motion because optimal motion complexity is crucial to normal motor development and less complex behaviors might represent repetitive motor behaviors, a core diagnostic symptom of ASD. As proof of concept, the relationship of the motion complexity measure to developmental outcomes was examined in a small set of HR infants. Results: HR infants with a later diagnosis of ASD show lower motion complexity compared to those that do not. There is a stronger correlation between motion complexity and ASD outcome compared to outcomes of cognitive ability and adaptive skills. Conclusions: Objective measures of motor development are needed to identify characteristics of atypical infant motor function that are sensitive and specific markers of later ASD risk. Motion complexity could be used to track early infant motor development and to discriminate HR infants that go on to develop ASD.

中文翻译：

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使用可穿戴传感器技术测量自闭症谱系障碍高家族风险婴儿的运动复杂性

背景：据报道，运动功能障碍是自闭症谱系障碍 (ASD) 高家族风险婴儿（HR 婴儿）非典型发育的最初迹象之一。然而，研究表明关于运动功能障碍的性质以及它是否可以预测以后的 ASD 诊断的结果不一致。这可能是因为当前的标准化运动评估可能无法识别出临床上可观察到的运动功能障碍之前的细微和特定的运动障碍。运动发育的定量测量可以通过提供对婴儿期细微运动差异的客观评估来解决这些限制。方法：我们使用 Opal 可穿戴传感器纵向评估 HR 婴儿的全天运动活动，并开发运动复杂性的测量方法。我们关注运动的复杂性，因为最佳运动复杂性对正常运动发育至关重要，而不太复杂的行为可能代表重复性运动行为，这是 ASD 的核心诊断症状。作为概念证明，在一小部分 HR 婴儿中检查了运动复杂性测量与发育结果的关系。结果：较晚诊断为 ASD 的 HR 婴儿与未诊断的 HR 婴儿相比，表现出较低的运动复杂性。与认知能力和适应技能的结果相比，运动复杂性和 ASD 结果之间的相关性更强。结论：需要对运动发育进行客观测量，以确定非典型婴儿运动功能的特征，这些特征是后期 ASD 风险的敏感和特异性标志物。