Gifted Issues Discussion homepage Forums Identification, Testing & Assessment significant relative weakness

Hello,

My DS (currently in 3rd grade) had a neuro psych eval done last fall for some ADHD concerns (which were confirmed)

In the WISC IV results, there was something that jumped out. He had a significant relative weakness in processing speed
VCI - 132 (98)
- abstract verbal reasoning (99.6)
PRI - 125 (95)
WMI - 126 (96)
PSI - 80 (9)

We had suspected some attention issues to be certain, but would never have guessed such a discrepancy. Is something like this common?

Could there be some other explanation for the test results?

He has always seemed like a very quick kid to us. He finishes his homework in a flash typically.

I think there can be different reasons for a lower PSI score. my older kid has ADHD and you can see obvious slow processing, in that if you ask her 8X7 she will typically stare blankly at you for several seconds before answering. Her writing is very slow, it took her ages to do her cursive writing packet for school. PSI requires copying symbols from a key for the coding section so a kid who writes slowly isn't necessarily going to do well. My younger kid has fine motor issues and even though he is mentally quick (at least, quicker than his sibling), he would not do well on any test that is timed and requires motor ability to do well. Some kids may also have visual tracking issues affecting the score.
You can easily test this by putting a pencil about a foot in front of his face, moving it slowly around, and asking if he ever sees a double image, or two pencils tracking it with his eyes. (I know someone is going to say that's not an accurate test, which is probably true, but it would flag issues that are obvious and severe, I think).

Slow processing speed tends to be more of a symptom than a cause, so it can look very different in different kids, depending on the underlying reasons for it. Furthermore, as blackcat explains above, there are many unrelated things that can result in a low processing speed score, like fine motor or visual processing issues. That said, lower processing speed (and often lower working memory), are usually found in people with ADHD, so your results are quite "normal" in that respect.

To blackcat's quick and dirty visual processing check, I would add: use pencils with something on the ends (e.g. eraser or toy) for child to focus on, and then: (1) Do slow (and increasingly larger) figure eights from left to right and see if both eyes follow together, and smoothly. (2) Slowly move a pencil from centre of face, about a foot out, to nose and back out, and see if eyes smoothly turn in and eventually cross and then move back. (3) Have child look back and forth between two different pencil ends on command (e.g. blue, red, red, blue....), and see if they can smoothly move eyes from one to the other - and then hold eyes in place until next command. These tests won't catch everything, but they're a good start.