Kylliäinen Anneli, Braeutigam Sven, Hietanen Jari K, Swithenby Stephen J, Bailey Anthony J
Human Information Processing Laboratory, Department of Psychology, FIN-33014 University of Tampere, Finland.
Eur J Neurosci. 2006 Nov;24(9):2679-90. doi: 10.1111/j.1460-9568.2006.05132.x.
Face and gaze processing were studied using magnetoencephalography in 10 children with autism and 10 normally developing children, aged between 7 and 12 years. The children performed two tasks in which they had to discriminate whether images of faces presented sequentially in pairs were identical. The images showed four different categories of gaze: direct gaze, eyes averted (left or right) and closed eyes but there was no instruction to focus on the direction of gaze. Images of motorbikes were used as control stimuli. Faces evoked strong activity over posterior brain regions at about 100 ms in both groups of children. A response at 140 ms to faces observed over extrastriate cortices, thought to be homologous to the N170 in adults, was weak and bilateral in both groups and somewhat weaker (approaching significance) in the children with autism than in the control children. The response to motorbikes differed between the groups at 100 and 140 ms. Averted eyes evoked a strong right lateralized component at 240 ms in the normally developing children that was weak in the clinical group. By contrast, direct gaze evoked a left lateralized component at 240 ms only in children with autism. The findings suggest that face and gaze processing in children with autism follows a trajectory somewhat similar to that seen in normal development but with subtle differences. There is also a possibility that other categories of object may be processed in an unusual way. The inter-relationships between these findings remain to be elucidated.
利用脑磁图技术对10名患有自闭症的儿童和10名发育正常的儿童（年龄在7至12岁之间）的面部和注视处理进行了研究。这些儿童执行了两项任务，在任务中他们必须辨别成对依次呈现的面部图像是否相同。图像展示了四种不同类型的注视：直视、目光转移（向左或向右）以及闭眼，但没有要求他们关注注视方向。摩托车图像用作对照刺激物。在两组儿童中，面部在大约100毫秒时均在后脑区域诱发了强烈的活动。在140毫秒时，两组儿童在纹外皮层观察到对面部的反应，该反应被认为与成年人的N170同源，反应较弱且呈双侧性，自闭症儿童的反应比对照儿童稍弱（接近显著水平）。在100毫秒和140毫秒时，两组对摩托车的反应有所不同。在发育正常的儿童中，目光转移在240毫秒时诱发了一个强烈的右侧化成分，而在临床组中则较弱。相比之下，直视仅在自闭症儿童中在240毫秒时诱发了一个左侧化成分。研究结果表明，自闭症儿童的面部和注视处理过程遵循的轨迹与正常发育过程有些相似，但存在细微差异。其他类别的物体也有可能以异常方式进行处理。这些研究结果之间的相互关系仍有待阐明。
