Vagal Tone and Social Behaviors in Autism

描述（由申请人提供）：本研究将探讨自闭症儿童与非自闭症儿童在迷走神经张力测量上的差异。迷走神经张力是衡量呼吸窦性心律失常的指标。这种心率的变化是由脑干区域通过第十脑神经（迷走神经）内的连接来控制的。迷走神经张力被认为反映了人类社会参与系统的一个基本部分。高迷走神经张力被认为反映了与环境接触的准备。此外，迷走神经张力对环境事件的反应变化表明儿童对这些事件的注意力和/或反应。本研究旨在通过检查自闭症儿童的迷走神经张力来更好地了解自闭症的生物学基础。过去对自闭症儿童心脏反应的研究并没有检查迷走神经张力。之前的研究已经检测了自闭症患者的其他心率指标，但没有对比儿童对社交和非社交事件的反应。过去的研究也没有检查心脏测量和自闭症核心缺陷区域测量之间的关系，比如联合注意力缺陷。在这项研究中，自闭症儿童和一个比较样本将在一个实验中被观察到，这个实验将以特定的方式改变社会刺激的类型。行为分析将涉及不同的条件，这些条件取决于刺激是社会性的还是物理性质的，以及事件是侵入性的还是非侵入性的。B-START应用的中心目标是完善和校准这种行为分析，并提供在这些条件下迷走神经张力差异的初步测试。共同注意行为也将被测量。统计分析将检验(1)自闭症儿童的迷走神经张力基线是否存在差异；(2)他们的迷走神经张力对社会事件的反应方式是否存在差异；(3)迷走神经张力是否与联合注意行为有关。这项研究可能提供自闭症社会缺陷的生物学基础信息，也可能有助于开发可用于研究婴儿期自闭症的方法。

DESCRIPTION (provided by applicant): This study will investigate whether children with autism differ from non-autistic children on measures of vagal tone. Vagal tone is a measure of respiratory sinus arhythmia. This variability in heart rate is controlled by regions of the brainstem via connections within the tenth cranial nerve (the vagus). Vagal tone is thought to reflect a fundamental part of the human social engagement system. High vagal tone is thought to reflect a readiness to engage with the environment. In addition, changes in vagal tone in response to environmental events indicate the child's attention and or reactivity to these events. This study seeks to better understand the biological bases of autism by examining vagal tone in young children with Autistic Disorder. Past research on cardiac responses in children with autism has not examined vagal tone. Previous research has examined other heart rate measures in autism, but has not contrasted children's reactions to social and nonsocial events. Nor has past research examined relations between cardiac measures and measures of core deficit areas in autism, such as joint attention deficits. In this study, children with autism and a comparison sample will be observed in an experiment that will vary the type of social stimulation in specific ways. The behavioral assay will involve conditions that vary with respect to whether stimuli are social or physical in nature, and whether the events are intrusive or non-intrusive. A central goal for this B-START application will be to refine and calibrate this behavioral assay, as well as to provide an initial test of differences in vagal tone during these conditions. Joint attention behaviors will also be measured. Statistical analyses will test (1) whether children with autism will differ in baseline vagal tone, (2) whether they will differ in the way that vagal tone changes in response to social events, and (3) whether vagal tone is related to joint attention behaviors. This study may provide information on the biological basis of the social deficits in autism and may also help develop methods that can be used to study autism in infancy.