In light of the known visuoperceptual strengths and altered language skills in autism, we investigated the impact of problem content (semantic/visuospatial) combined with complexity and presence of lures on fluid reasoning in 43 autistic and 41 typical children (6-13 years old). Increased complexity and presence of lures diminished performance,…

Individuals with autism spectrum disorders (ASDs) have been assumed to show evidence of abnormal visuospatial processing, which has been attributed to a failure to integrate local features into coherent global Gestalts and/or to a bias towards local processing. As the available data are based on baseline performance only, which does not provide…

Difficulties in visual attention are often implicated in autism spectrum disorders (ASD) but it remains unclear which aspects of attention are affected. Here, we used a multiple object tracking (MOT) task to quantitatively characterize dynamic attentional function in children with ASD aged 5-12. While the ASD group performed significantly worse…

Thirteen autistic and 14 typically developing children (controls) imitated hand/arm gestures and performed mirror drawing; both tasks assessed ability to reorganize the relationship between spatial goals and the motor commands needed to acquire them. During imitation, children with autism were less accurate than controls in replicating hand shape,…

Children diagnosed with Pervasive Developmental Disorder Not Otherwise Specified (PDD-NOS) and Asperger Syndrome (AS) may be characterised by a similar perceptual focus on details as children with autistic disorder (AD). This was tested by analysing their performance in a visuoperceptual task [the Children's Embedded Figure Test (CEFT)] and a…

Background: The executive functions of inhibition, planning, flexible shifting of actions, and working memory are commonly reported to be impaired in neurodevelopmental disorders. Method: We compared these abilities in children (8?12 years) with high functioning autism (HFA, n = 17), attention deficit-hyperactivity disorder (ADHD, n = 21) and…

Analysis of the conceptions of spatial relations, size comparisons, and gesture imitations of 16 autistic children (ages 6-14 years) with IQs over 70 indicated an inability to acquire concepts of size comparison and spatial relationships through verbal instructions, suggesting a cognitive deficit of impaired symbolic-representational functioning.…