I have a dd who had really low scores on two WISC subtests which was traced to a vision issue (double vision, tracking, lack of peripheral vision) - all muscle-function related. She went through a long course of very successful vision therapy - within just one month of starting it was obviously making a difference. We haven't retested with a WISC, but she's had the WJ-III Cognitive Abilities test post-vision therapy and the subtests on the WJ-III that rely on vision were all up in the same range as her other scores. FWIW, it's also brought her scores on state testing and other types of achievement tests up too - there was a subtle visual component going on that was impacting scores across the board as well as impacting her ability to learn up to her full ability in the classroom.
If the tester feels it's possibly a problem with tracking/etc - imo, it's definitely worth looking into
polarbear
