One of the characteristics of autism spectrum disorder (ASD) is atypical sensory processing and perceptual integration. Here, we used an object naming task to test the significance of deletion of vertices versus extended contours (edges) in naming fragmented line drawings of natural objects in typically developing and ASD children. The basic components of a fragmented image in perceptual closure need to be integrated to make a coherent visual perception. When vertices were missing and only edges were visible, typically developing and ASD subjects performed similarly. But typically developing children performed significantly better than ASD children when only vertex information was visible. These results indicate impairment of binding vertices but not edges to form a holistic representation of an object in children with ASD.
We asked typically developing and ASD subjects to name fragmented visual objects with either missing vertices or elongated edges. We found that when the vertices were missing and only objects' edges were visible, typically developing and autistic subjects' performances were similarly low. But more importantly, ASD children performed significantly worse than typically developing children in naming the fragmented images of objects when only vertices were available. These findings indicate atypical visual processing in ASD individuals. Although the cause of this impairment is not clear and needs further investigation, the potential candidates are impairment in integration of fragmented information due to malfunctioning of neural oscillation, impaired STDP, biased local processing, and image-based object representation in ASD individuals.