Cue the graphic, courtesy of DANDA:
Click here for a better look. (I couldn't quite figure out how to smoosh the graphic into blogger, and preserve the aspect ratio.)
I blogged about the basics of DCD here. The official term is DCD but it is often referred to as "dyspraxia." Its defining quality is poor coordination. However, there is a statistically significant correlation between DCD, and language and social impairment, as well as a litany of other cognitive issues such as poor working memory and poor ability to multitask.
As the graphic illustrates, Developmental Coordination Disorder/Dyspraxia and Autistic Spectrum Disorder are interlocking sets, meaning many individuals have symptoms of both. However, technically, from a diagnostics perspective, an individual cannot have both. That is, if an individual presents with PDD-NOS, DCD is ruled out as a discrete diagnosis. In her "impression" report, Brad's developmental pediatrician indicated an impression of PDD-NOS, and that he tested "signficant for" hypotonia and DCD, but the final diagnosis was PDD-NOS, not DCD.
Anecdotally, many individuals with asperger's and autism identify as "dyspraxic" even though it's not an official diagnosis.
If I were to put Brad on the graphic, I'd place him in the interlocking set between ASD and DCD, closer to the DCD side than the ASD side. And if I were to hazard a guess, I'd say he's going to cross from the interlocking set into the "pure" DCD bubble some time before he turns 6. (In August 2008, Brad's ADOS score was at the cutoff. Plus he has strength in the social domain, a predictive factor for growing out of the diagnosis. For these reasons, I think there's a very strong chance Brad will lose the PDD diagnosis.)
The graphic illustrates, in part, why I abandoned the differential diagnosis. Is he in this bubble or that bubble? In reality, the lines are blurry, the bubbles intersect with each other and Brad's brain is going to change over time. The bottom line is that he's neurologically different. What label is ascribed to that difference at any point and time is less valuable and probative than the overall developmental trajectory.
What does DCD mean to Brad? I blogged about it a bit here. For starters, he walks like he's drunk. Much less so today than 6 months ago, but he still has an uneven gait. He's got terrible fine motor coordination. He's very floppy, low energy, and unmotivated to move. As an example, he never - and I mean never - stands up in his crib. (Yes, he is still in a crib.) To get him up in the morning or at nap, he needs a lot of prompting and assistance. He has never once stood up in his crib unprompted or unassisted. He drooled persistently until he was 2-1/2. He has poor depth perception and poor ability to track things visually.
Each person who has evaluated Brad has noted he splays his fingers. Here's video of it. As I understand it, this is a result of low tone in his fingers and is an indication that he may have difficulty grasping a pencil in the future. The good news on that front is that there are very specific and effective therapies to develop grasping strength
On the speech front, he has delays and motor issues, such as getting stuck on the first syllable (like stuttering), and more recently "elongation" in the middle of a word or a sentence.
Last, he also is very slow at processing information, sensory data, social cues and language. More on that later.