analysis of attention disorder and response inhibition among autism spectrum disorders, mental retardation and normal children

background: previous researches have shown that children with autism spectrum disorder and mental retardation have some dysfunctions in attention and inhibition functions. the present study evaluated the performance of attention and response inhibition in autism spectrum disorders, mental retardation and normal children.  methods: the method of this study was ex post factor, so 15 children with autism spectrum disorder, 15 children with mental retardation and 15 normal children were selected through stroop neuropsychological test and cpt. data analysis was performed by using methods of anova and lsd post hoc test and kruskal-wallis non-parametric via spss-17. results: data analysis showed that there is a significant difference among the three groups in the function of selective attention (p<0/0001) and inhibition (p<0/0001). in addition, it clearly illustrated that there is no significant difference between children with autism and mental retardation (p<0/535) in the components of continuous performance test. furthermore, a significant difference was observed between autism and normal children (p<0/0001), and   mentally retarded and normal children (p<0/0001)  conclusion: based on the components attention and response inhibitions were significantly different among the three groups; consequently, the performance of mental retarded children were weaker than autism spectrum disorder and normal children and the performance of  children with autism spectrum disorders were weaker than normal children.