Autism and Asperger's syndrome.

Knowledge about the spectrum of autistic disorders, including Asperger's syndrome, has grown significantly. Diagnoses can be made more reliably and there is better characterization of elements within the spectrum than ever before. A clearer picture of the cognitive limitations displayed by persons with conditions in the autistic spectrum is emerging. Deficits in manipulating abstract meanings, translating principles across contexts, and attending to contextual meanings can be seen in lower and higher functioning individuals. Links between "executive function," "theory of mind," and findings from functional imaging are becoming apparent. There are consistent indications that frontal and temporal regions play a crucial role in these disorders. Associations with specific genetic defects has been suggested, but methods capable of discovering the complex interplay of several genes will be needed before generalized conclusions can be reached.