The processing speed index (PSI) of the Wechsler intelligence scale for children (WISC-IV) has been found to predict a child's level of academic functioning. The consistently reported PSI weakness in children with autism spectrum disorder (ASD) therefore warrants special assistance and attempts at compensation for the disadvantages associated with…

Relationships between sluggish cognitive tempo (SCT) and age and IQ were investigated in children with autism and/or ADHD covering broader age and IQ ranges than in previous studies. Mothers rated 1436 children with autism and 1,056 with ADHD (2-17 years, IQs 9-149) on Pediatric Behavior Scale SCT items. Increasing age correlated with SCT in the…

Academic achievement patterns and their relationships with intellectual ability, social abilities, and problem behavior are described in a sample of 30 higher-functioning, 9-year-old children with autism spectrum disorder (ASD). Both social abilities and problem behavior have been found to be predictive of academic achievement in typically…

It was found that the levels of toilet training, eating skills, participation in group activities, and self-control in the autistic children improved significantly with age. The skills of number concepts in the autistic children also improved with age. (Author)

Assessment of 21 males (ages 4-27) with fragile X syndrome found that subject's age was associated with age-equivalent levels of both simultaneous processing and achievement, but not with levels of sequential processing. A smaller longitudinal study confirmed the presence of a plateau in sequential processing after the age of 10 years. (Author/JDD)

This study examined the relationship between (1) sex and family size of 33 siblings of autistic children; and (2) siblings' performance on achievement, self-concept, home behavior, and school behavior measures. Overall, the siblings' performance was not suggestive of a need for special intervention. (Author/JDD)