3, Wilson, 2005, par. 4). In fact, the similarities between these disorders are so extensive that many experts maintain there is no substantive diagnostic distinction between them. "The frequently posed question is whether these disorders should be conceptualised (sic) as part of a single continuum or whether they are distinct diagnostic entities" (Dissanayake, 2004, par. 2).
The differences between AS and HFA are thought by some experts to be merely quantitative, not qualitative, such that they are limited to varying degrees of the same symptoms. Nevertheless, a careful review of current literature on the subject reveals that there are some very real, qualitative differences between Asperger's and HFA. In fact, it can be argued that the core symptoms of these disorders are diametrically opposed - that the main indicators of the disorders are mutually exclusive. Should someone with AS be wrongly diagnosed with HFA, or vice versa, the repercussions for sufferers of these conditions could be significant. The appropriate treatment for HFA will not be exactly the same as that for AS. To treat the conditions as one and the same would risk putting AS sufferers at a severe disadvantage in their development, as AS requires unique learning supports and social coaching that differs from the treatment required for HFA.
According to Lyons and Fitzgerald (2004), "autism and Asperger syndrome are both recognized neuro-developmental disorders that are defined primarily in behavioral terms. Autistic disorder and Asperger's are both marked by "qualitative impairment in social interaction" (Tucker, 2006, par. 11). Symptoms of such impairment include difficulty with non-verbal social cues such as facial expression, body language, and gestures; difficulty developing appropriate peer relationships; failure to spontaneously seek others to share interests or achievements; and/or "lack of social or emotional reciprocity" (par. 11). Both disorders are also marked by "restricted, repetitive, and stereotyped patterns of behavior, interests, and activities," including abnormally intense preoccupation with stereotyped or restricted patterns of interest; obsessive adherence to nonfunctional routines or rituals; "stereotyped and repetitive motor mannerisms;" or "persistent preoccupation with parts of objects" (par. 12). Those with two of the social interaction impairment symptoms and one of behavioral symptoms listed above may be clinically diagnosed with Asperger's Syndrome, "characterized by autistic social dysfunction and idiosyncratic interests, in the presence of normal intelligence" (Ghaziuddin & Mountain-Kimchi, 2004).
Dissanayake (2004) maintains that HFA and AS are qualitatively very similar disorders. She states that "the findings from the comparative literature are either marked by an absence of differences or by only quantitative differences between the two groups, such that most symptoms, associated features and biological indices are either shared or overlapping to some degree" (par. 3). Furthermore, any differences between the two disorders become less apparent with age. "Specifically, it has been found that children with these disorders show greater differences in the manifestation of impairments in social interaction, communication, motor skills and repetitive behaviours (sic) during the early childhood years than during middle childhood and adolescence. The main direction of difference during the preschool years is that those with autism