DD has almost a 60 point gap between processing speed and perceptual reasoning. If you calculate extended norms, coding was an 8 and matrix reasoning was a 22.
She has ADHD which I think explains most of it in her case.She can also be perfectionistic and will refuse to move on until she knows she has the right answer. The psych who assessed her also said that she is probably a visual-spatial thinker because of her high perceptual reasoning (around 150) and kids who think in images tend to have problems with processing speed because they have to convert back and forth between pictures and words in their minds.
DD seems to be really slow with writing so I'm taking her in for an ocupational therapy assessment to make sure we're not missing something in terms of problems writing or hand-eye coordination.
She just turned 8 and is currently knitting a scarf, so I doubt anything will turn up with that eval, but I just want to have it and rule it out as an issue.

DS also had low processing speed, but at 109 it wasn't as bad. In his case, he has obvious fine motor issues (dyspraxia).