So, considering the symbol search task specifically...
It is supposed to tap visual scanning and discrimination in particular. This would suggest his low scores are perhaps due to a visual perception issue, which would be supported by the many reversals he makes in his writing. However, wouldn't it be evident in other tasks? It seems like visual scanning and discrimination is a pretty foundational ability that would come to play in block design, visual puzzles, matrix reasoning, figure weights, etc. But maybe I just don't understand it all.
My reason for continuing to ruminate on the issue is that I want to know whether he has some visual perception issue (which based on his scores seems like it would be pretty extreme and require some specific remediation) or to know if I should request an alternate subtest to clarify.
