Fluid and Crystallized Intelligence in High Functioning Autism and Asperger Syndrome

Intelligence in autistic spectrum disorders, especially high functioning autism and Asperger's syndrome has been the subject of numerous investigations that seek to establish intellectual ability observed in these subjects. Some of the most outstanding results indicate that fluid intelligence is one of the aspects of superior performance in this population compared to tests that measure crystallized intelligence such as the Wechsler scales, providing a reason for using in intelligence studies instruments that measure abstract reasoning and the analogical capacity, closely related to fluid intelligence function, one of this like the Raven progressive matrices. In the present research we evaluated 12 children with high functioning Autism and 6 with Asperger's syndrome through the WISC-IV and the Raven test. The results showed there are no significant differences between both measures of intelligence. However, we found that there are differences in the intellectual profile of both groups and that Asperger's syndrome appears to have a better intellectual level compared with high functioning Autism.