BACKGROUND One of the main diagnostic features of individuals with autism spectrum disorders is nonverbal behaviour difficulties during naturalistic social interactions. The 'Interactional Heterogeneity Hypothesis' of ASD proposes that the degree to which individuals share a common ground substantially influences their ability to achieve smooth social interactions. METHODS To test this hypothesis, we filmed 29 autistic and 29 matched typically developed adults engaged in several conversational tasks. Windowed cross-lagged correlations were computed using the time series of motion energy of both individuals in a dyad. These coefficients were then compared across the three dyad types that were homo- or heterogenous with respect to diagnosis: pairs of two autistic individuals, two typically developed individuals or pairs of one autistic and one typically developed person. RESULTS We found that all dyad types achieved above-chance interpersonal synchrony, but that synchrony was more expressed in typical dyads compared to both autistic and mixed dyads. LIMITATIONS The method presented here provides only one, albeit objective and robust, approach to explore synchrony. The methodological choices as well as the lack of consideration for other communication modalities may limit our interpretation of the findings. Moreover, the sample size is small with respect to exploring associations between synchrony and various outcome and social skill measures. CONCLUSIONS The present results do not provide support for the Interactional Heterogeneity Hypothesis given that autistic individuals do not coordinate better when interacting with another autistic individual, compared to when interacting with a typical individual.

中文翻译：

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自闭症谱系障碍中非语言人际同步性的减少与伴侣诊断无关：运动能量研究。

背景自闭症谱系障碍患者的主要诊断特征之一是自然社交互动过程中的非语言行为困难。自闭症谱系障碍的“互动异质性假说”提出，个体拥有共同点的程度会极大地影响他们实现顺利社交互动的能力。方法 为了检验这一假设，我们拍摄了 29 名自闭症患者和 29 名匹配的正常发育成年人参与多项对话任务的情况。使用二人组中两个个体的运动能量的时间序列来计算窗口交叉滞后相关性。然后将这些系数在诊断方面同质或异质的三种二元类型中进行比较：两个自闭症患者对、两个典型发育个体或一个自闭症患者和一个典型发育个体对。结果我们发现所有二人组类型都实现了高概率的人际同步，但与自闭症和混合二人组相比，这种同步在典型二人组中表现得更多。局限性这里提出的方法仅提供了一种探索同步性的方法，尽管客观且稳健。方法的选择以及缺乏对其他沟通方式的考虑可能会限制我们对研究结果的解释。此外，在探索同步性与各种结果和社交技能测量之间的关联方面，样本量很小。结论 目前的结果并没有为互动异质性假说提供支持，因为与与典型个体互动相比，自闭症个体在与另一个自闭症个体互动时并不能更好地协调。