Wow! .9 correlation at iq>160?
That means people at extremely high IQs, the brain has a hard time balancing high functioning in all general areas, and actually starts depleting some parts of the cortex. The brain is essentially at full capacity and must balance this by having weak areas resulting in SLDs, ASP, and ADHD, dyslexia etc.
I wouldn't leap to that conclusion. While I don't know the reason for this high correlation, one might speculate that
a) Exceptionally gifted individuals have brains that are somehow physiologically different from neurotypicals. This might mean that the brain is wired to do certain things really well but other things not so well. (e.g. a sports car vs. a hybrid vs. a tow truck when considering speed, gas mileage, and brute power)
b) Brains are remarkably plastic, especially in childhood. It's possible that some extremely gifted individuals focused on building certain skills to the detrimental neglect of others. This may be neither inevitable nor permanent but would require work to remedy (e.g. OT, PT etc; or earlier just guiding the child to spend time developing skills that don't interest them as much).
Both a) and b) might be completely wrong, but I wouldn't leap to conclusions without solid research. Also fwiw my understanding is that from fMRI studies etc we appear to use our brains far below their full capacity.
