I definitely wouldn't be paying a lot of money given the current research state, even if my child were on board:

http://en.wikipedia.org/wiki/scotopic_sensitivity_syndrome

Does your son think there is a problem? What does he think is going on? (How) have you ruled out ADD, since you say he has ADD-like symptoms, and under-challenge, given the high scores?

If you really want to try the colour thing, I'd buy cheap coloured overlays and let him experiment with them.

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