The authors study specific participation of parvo- and magnocellular visual processing pathways in image formation in preschool children with atypical development.

In comparison with typically developing children, children with autism spectrum disorder (ASD) and mental retardation (MR) had higher thresholds of contrast detection during sequential change; higher thresholds were observed only in high ASD cases. Global motion thresholds were lower in children with MR and low ASD. Children with high ASD could discern stimuli only with their slow shift.

In MR and low ASD cases, figure recognition time increased only with increasing number of locations of targets among demonstrated figures. Children with high ASD demonstrated constant increase in detection time. The authors found correlations between visual processing deficit severity and the language development level.