Apraxia and autism: what's the difference?
Autism was the label everyone used for Sam. Apraxia was the piece that explained what we were seeing.
In The Spellers Guidebook, Dawnmarie Gaivin and Dana Johnson describe apraxia as "a disconnect between intention and initiation." The thought is there. The body does not carry it out on command. Speech is output, and apraxia affects output, not input or understanding.
That distinction matters. What many experts labeled as behaviors or a learning disorder was apraxia. Sam was listening and understanding all along. He could not show it in the ways people were measuring.
The label told part of the story. Autism described part of Sam. Apraxia explained why a smart, aware young man could not speak his thoughts or follow a spoken direction on demand.
In one small 2015 Penn State study of 30 young children referred for speech or autism concerns, 63.6% of those first diagnosed with autism also had apraxia. If that number is anywhere close, a lot of families are having the same one-sided conversation we had for twenty years.
Questions
Can someone have apraxia without autism?
Yes. Apraxia shows up in other settings too. For Sam, the two sit together, and apraxia is the part that kept his understanding hidden.
Does apraxia mean low intelligence?
No. Apraxia affects output, not input or understanding. Intelligence and speech run on different tracks.