(excerpt from Romanczyk, R.G. (1994) Autism. In V.S. Ramachandran (Ed.) The Encyclopedia of Human Behavior. Academic Press: San Diego, Vol. 1, 327-336.)
"Autism is a developmental disorder that typically affects all major areas of functioning, with severity between areas and across individuals having a broad range of expression. Historically it has been associated with early onset, typically appearing by age 2 1/2. It is not a disease entity but rather a syndrome defined by behavior characteristics and patterns, and therefore most probably has multiple etiologies rather than a single causative factor. Autism remains a controversial disorder with respect to diagnosis, etiology, and treatment strategies. There are frequent examples of outrageous claims and distortions made by professionals, advocates, and the media. The tremendous gap between basic and applied research with typical clinical and educational practice, as well as treatment fads, places autism in a unique category. It often has severe impact upon individuals and families, is clinically complex, has an unusually large quantity of research relative to its prevalence, and is unmatched in the confusion, distortion and fraud found in service delivery.
The primary clinical characteristics of autism may be clustered into the broad domains of:
a. social behavior
c. cognitive development
d. interaction patterns
e. reaction to the environment
f. behavioral repertoire."