University of California, San Diego Autism Center of Excellence; Ulsan National Institute of Science and Technology, South Korea.
University of California, San Diego Autism Center of Excellence.
J Am Acad Child Adolesc Psychiatry. 2019 Oct;58(10):1004-1015. doi: 10.1016/j.jaac.2018.12.011. Epub 2019 Mar 6.
Unusual eye contact is a common clinical feature in autism spectrum disorder (ASD), yet eye-tracking studies that quantify eye fixation report inconsistent results, possibly because of small samples, varied stimuli, and considerable heterogeneity of eye-region fixation even within typical development. Goals were to examine eye-region fixation levels in a large, very young cohort; the degree to which the presence of speech, hand gestures, and a geometric distractor influence eye-region fixation; and possible developmental changes across time.
In experiment 1, 385 toddlers (143 with ASD, 242 without ASD, 11-47 months old) watched an actress engaging in child-directed speech with hand gestures against a plain background. Ninety-one toddlers participated approximately 8 months later. In experiment 2, another 231 toddlers (74 with ASD, 157 without ASD, 12-47 months old) watched the same video, but with embedded geometric distractors. Total fixation duration on facial and body regions (eg, eyes, hands) and geometric distractor regions (experiment 2 only) while the actress was speaking or silent, with or without gesturing, was examined, as were relations with clinical traits.
Overall, across the 2 experiments and the 2 cross-sectional and longitudinal samples, eye-region fixation duration did not differ between toddlers with and without ASD, although fixation toward the face overall was decreased in toddlers with ASD. This decrease became more apparent with the presence of geometric distractors (experiment 2) as indexed by a geometric preference score, and this score was associated with autism severity.
Within the context of viewing child-friendly vignettes, decreased eye-region fixation does not reliably characterize toddlers with ASD. An index of competition between faces and external distractors might be a more robust measure.
不寻常的眼神接触是自闭症谱系障碍（ASD）的常见临床特征，但量化眼部注视的眼动追踪研究报告结果不一致，这可能是由于样本量小、刺激物不同以及即使在典型发育中眼部区域注视的异质性很大。目标是在一个大型、非常年轻的队列中检查眼部区域注视水平；言语、手势和几何干扰物的存在对眼部区域注视的影响程度；以及随时间的可能发展变化。
在实验 1 中，385 名幼儿（143 名自闭症，242 名非自闭症，11-47 个月大）观看女演员用手势进行儿童导向的演讲，背景为纯色。91 名幼儿大约 8 个月后参与。在实验 2 中，另外 231 名幼儿（74 名自闭症，157 名非自闭症，12-47 个月大）观看了相同的视频，但嵌入了几何干扰物。当女演员说话或不说话时，观察她说话或沉默时对面部和身体区域（例如眼睛、手）和几何干扰物区域（仅实验 2）的总注视持续时间，以及与临床特征的关系。
总的来说，在 2 个实验和 2 个横断面和纵向样本中，自闭症和非自闭症幼儿的眼部注视持续时间没有差异，尽管自闭症幼儿整体对面部的注视减少。当存在几何干扰物（实验 2）时，这种减少变得更加明显，这可以通过几何偏好得分来表示，并且该得分与自闭症严重程度相关。
在观看儿童友好的小插图的背景下，自闭症幼儿的眼部区域注视减少并不可靠地描述。面部和外部干扰物之间竞争的指标可能是更稳健的衡量标准。
