This study examined perceptual distortion of visual illusions in children with autism spectrum disorder (ASD) and age-, sex- and IQ-matched typically developing children to determine whether local bias exists in low-level visual processing in ASD as the weak central coherence (WCC) theoretical account predicts. To explore whether higher-level contextual information can be integrated with low-level information in ASD, the perception with and without perspective cues was also examined. The children with ASD succumbed to illusions to a lesser degree than did the comparison group, and the degree of perceptual distortion was negatively correlated with Block Design score, a marker of WCC. The presence of perspective cues did not increase perceptual distortion among both groups to a statistically significant degree. The results support the WCC account suggesting abnormalities in integrating visual information in low-level processing in individuals with ASD when they perceived illusory figures.

Key words: autism spectrum disorder, visual illusion, weak central coherence, low-level perceptual processing