Okay, this theme interests me as it has come up in a recent thread I started. Doing a bit of reading about it on the net, I found what seems to me an excellent article by a doctor from something called the Asperger's Association of New England. He starts out by saying that the territory of the two conditions is muddy and not clear, so that certainly goes along with what IC and MWM are saying. However, my niggling gut feeling and judgement all the time is that there IS a clear, discernible difference between the two and he clarifies this for me. I'd like to post it here because I think it's so helpful and it really caused a kind of "oh, yeah, that's what I'm trying to say" lightbulb to go off.
"The problem with the ADHD and Asperger overlap, is that at the more severe margins of the ADHD spectrum and the less extreme margins of the Aspergers spectrum, clinicians can legitimately argue for one over the other diagnosis. Nonverbal Learning Disability (NLD) is not the only confusing label at the milder side of Aspergers Syndrome. Many children with significant ADHD can be quite socially aberrant, lack perspective-taking skills, have severe sensory integration problems, be absolutely obsessed with Nintendo, talk constantly and too loudly, have meltdowns at the drop of a hat, be teased, and have no friends.
Yet even in this confusing part of the disruptive disorder stew, where perhaps juvenile bipolar disorder is one click further out than severe ADHD, there are still some guidelines I use to help me sort through the Aspergers versus ADHD dilemma. First and foremost, Aspergers Disorder is one of the Pervasive Developmental Disorders. As hard to digest as Pervasive Developmental Disorder (PDD) has been for all of us working the Autistic Spectrum, the term nevertheless clearly and plainly denotes that children who fall into this category have developmental delays that pervade many developmental sectors. Therefore I expect, in fact require, a child with Aspergers Syndrome to have at least a history of delays and deviations in many sectors (for example, possibly in gross motor, fine motor, sensory integration, attentional regulation, pragmatic speech, socialization, interest and play, affective modulation (e.g., anxiety and mood management), and neurocognition.
It is not that children with ADHD do not have developmental delays, but they do not usually have the variety, the severity, and the contours that children with Aspergers Disorder characteristically have. ADHD children can have (although certainly not always) poor social skills, but they rarely and consistently have the demonstrable defects in comprehending social reciprocity (e.g., impairments in theory of mind, understanding of complex nonverbal cues, defects in facial recognition, distortion of subtle affective displays, miscomprehension of social context and signaling , and so forth.) Children with ADHD can talk in annoying controlling ways, but the configuration of pragmatic mis-broadcasting that is so tell-tale at any gathering of individuals with Aspergers Syndrome is really quite consummate and unmistakable. This combination of prosody, dysfluency, pitch and volume, gaze aversion, fascinating but unfunny humor, peculiar word usage, anthropomorphizing of objects, hypersensitivity to criticism, receptive distortion of tones of voice, is certainly highly variable from one individual to another, but it is often definitive in whatever unique madras pattern it appears.
In general, children with Aspergers Syndrome have more than most children with ADHD. They have more perseveration, more stereotypies, more splinter skills, more trouble telling a coherent story, and more neuro-integrative problems.
Children with ADHD can have as bad or worse executive functioning skills as the children with Aspergers. If their attention is very, very poor, children with ADHD can have as bad a Rey Osterreith. In fact, children with ADHD can often have verbal IQ which are much better than their performance IQs (like the Aspies and NLDers), but more often it is due to very slow processing speed, which drags down the timed tests and deflates the scoring of Performance IQ. Indeed, many individuals with ADHD share a great many neurocognitive features with children with Aspergers Syndrome, and that is one reason why neuropsychological testing by itself is not the best way to make a diagnosis of Aspergers Syndrome. Testing is often incredibly helpful in understanding the learning style of the child with Aspergers, and it is unarguably essential in making a diagnosis of NLD.
Children with Aspergers Disorder and children with ADHD usually want to have friends. Both groups have poor rite-of-entry skills and both groups play badly. Yet both groups usually fail socially for different reasons. Their recipes for play failures have different ingredients. What often turns on a child with Aspergers Syndrome is behavior so unusual and idiosyncratic that it can be unfathomable even to another child with Aspergers. Children with ADHD frequently break rules they understand, but defy and dislike. Children with Aspergers Syndrome like rules, and break the ones they dont understand. They are ever alert to injustice and unfairness and, unfortunately, these are invariably understood from their own nonnegotiable perspective. Children with ADHD are often oppositional in the service of seeking attention. Children with Aspergers disorder are oppositional in the service of avoiding something that makes them anxious. Both groups have serious sensory integration problems, can be uncoordinated and impulsive, and they both very much respond positively to structure and routine. The children with Aspergers, however, crave order, hate discrepancy, and explode (or withdraw) in the face of violation of expectations. In this regard, they are enormously brittle and fragile. Children with Aspergers are much more tyrannized by details; they accumulate them, and cannot prioritize them. Children with ADHD also have poor organizational skills, but can be much more fluid in their thinking, more inferential in their comprehension, and less rigid in their treatment of facts that they are able to organize.
Of course these are all generalizations. There is always the child who is the exception. Whatever their profile, whatever their label, both the child with ADHD and the child with Aspergers syndrome require us to change our assumptions about relationships and our expectations about behavior. They are both demanding, confusing, exhausting, and frustrating. Inside, each is a child who needs tolerance, our informed understanding, our thoughtful interventions, our patience, and our love."
Ref: http://www.aane.org/asperger_resources/articles/miscellaneous/aspergers_or_adhd.html
