ARC Centre of Excellence in Cognition and its Disorders, School of Psychology, University of Western Australia, Australia.
Dev Sci. 2013 Jan;16(1):116-23. doi: 10.1111/desc.12007. Epub 2012 Dec 18.
Face identity aftereffects are significantly diminished in children with autism relative to typical children, which may reflect reduced perceptual updating with experience. Here, we investigated whether this atypicality also extends to non-face stimulus categories, which might signal a pervasive visual processing difference in individuals with autism. We used a figural aftereffect task to measure directly perceptual updating following exposure to distorted upright faces, inverted faces and cars, in typical children and children with autism. A size-change between study and test stimuli limited the likelihood that any processing atypicalities reflected group differences in adaptation to low-level features of the stimuli. Results indicated that, relative to typical children, figural aftereffects for upright faces, but not inverted faces or cars, were significantly attenuated in children with autism. Moreover, the group difference was amplified when we isolated the 'face-selective' component of the aftereffect, by partialling out the mid-level shape adaptation common to upright and inverted face stimuli. Notably, the aftereffects of typical children were disproportionately larger for upright faces than for inverted faces and cars, but the magnitude of aftereffects of autistic children was not similarly modulated according to stimulus category. These findings are inconsistent with a pervasive adaptive coding atypicality relative to typical children, and suggest that reduced perceptual updating may constitute a high-level, and possibly face-selective, visual processing difference in children with autism.
自闭症儿童的面孔身份后效明显低于典型儿童，这可能反映了经验相关的知觉更新减少。在这里，我们研究了这种异常是否也扩展到非面孔刺激类别，这可能表明自闭症个体存在普遍的视觉处理差异。我们使用图形后效任务来测量典型儿童和自闭症儿童在暴露于扭曲的直立面孔、倒置面孔和汽车后直接进行知觉更新的情况。研究和测试刺激之间的大小变化限制了任何处理异常反映出群体对刺激低水平特征的适应差异的可能性。结果表明，与典型儿童相比，自闭症儿童的直立面孔的图形后效明显减弱，但倒置面孔和汽车的图形后效则没有减弱。此外，当我们通过分离与直立和倒置面孔刺激共有的中等级别形状适应来分离后效的“面孔选择性”成分时，组间差异被放大。值得注意的是，典型儿童的后效对于直立面孔的影响大于对于倒置面孔和汽车的影响，但自闭症儿童的后效则没有根据刺激类别进行类似的调节。这些发现与相对于典型儿童的普遍适应性编码异常不一致，表明知觉更新减少可能构成自闭症儿童的高级、可能是面孔选择性的视觉处理差异。
