Executive function in autism : a comparative study

The literature examining executive function (EF) in autism is reviewed. Current studies show that individuals who have autism demonstrate poor performance on EF measures, particularly in the area of cognitive flexibility. Theorists have suggested that EF is an underlying cognitive impairment in autism, responsible for a number of the symptoms observed in this disorder. However, the methodology used in existing research is problematic and future research is needed that examines EF in children who have autism using developmentally appropriate measures that account for the deficits observed in autism and that assess specific sub-components of EF. This study examines whether children who have autism and moderate learning disabilities perform less well than do a control group of children who have learning disabilities matched for age, verbal ability and non-verbal ability. Six EF measures were used: three existing EF measures, one modified measure and two specifically designed EF measures. Results indicated no significant differences between the experimental and matched control groups on any of the EF measures used. Findings challenge existing empirical evidence and do not support the notion of EF as an underlying impairment in autism. Future research is required that further examines sub-components of EF in the context of autism, development and learning disabilities.