While my son's scores on the WISC-IV are nowhere near as high as your son's, the pattern of highs and lows is very similar - high VCI, lower PRI, very low PSI. My son has significant fine motor deficits and some visual processing problems that are not picked up with an ordinary eye exam - left-sided visual neglect, scotopic sensitivity, problems with tracking and convergence, poor figure-ground discrimination, and so on. He also has formal diagnoses of Asperger's Syndrome and Disorder of Written Expression.

The problems with motor output, visual processing, and visual-motor coordination (which correspond to the very low PSI scores,and which adversely impacted the PRI) make it very difficult for him to write legibly, and even harder for him to write legibly and still think about the content of what he is writing while he is writing. When he was your son's age, my son really needed a scribe to record what he wanted to say: the mismatch between what he had in his head and what he was able to get out of it on paper was so huge that it was too frustrating for him to even try - trying to write by hand made him feel stupid and he felt that it was useless.

Kindergarten was miserable; he was constantly depressed and frustrated because everything was either too easy or too hard. This rapidly progressed to outright refusal or avoidance behavior when asked to do anything involving a writing task or really any visual or motor task that he didn't think he'd be able to do, or anything that he'd mastered so long ago that he felt it was insulting. He had a choice of trying to do the work and having evidence stare him in the face that he was incapable, or refusing and getting consequences for being disobedient, but not being ashamed of not being able to complete the written work acceptably (which he clearly saw was not difficult for others). He would rather have been seen as disobedient than as stupid. Refusing to work allowed him to preserve some shred of his self esteem, but at a huge cost. The consequences of being in this kind of a school situation were a big part of our decision to homeschool.

As he got older, he learned to use the keyboard independently, and that has worked reasonably well for him, but it doesn't for some kids.If what he is trying to write is very complex or difficult, he still benefits from using a scribe so that he doesn't have to concentrate at all on the motor planning part of things.

Based on my experiences with my own child, "work" that is appropriate to the PSI level or that requires a lot of motor output or handwriting, but is not at or at least near the challenge point for the VCI and PRI level is a recipe for disaster.

Specialized occupational therapy to help rehabilitate the visual issues was incredibly helpful in improving my son's reading speed and fluency, BTW.

There are other things besides motor skills deficits and visual problems that can cause a low PSI score, including ADHD, but I wanted to be sure you knew that ADHD is often not the main problem with a score profile like this.

I don't know if my son would count as one of Grinity's 10 gifted/Asperger's data points, but I wanted to put it out there for you.