It also had a strong correlation with math.
I find this very interesting as our string obsessed almost 4 year old seems much more interested in language/sciences and shows little interest at all in math (so far).
He has been learning violin and loves it. I love it because apart from any other reason he has to practice and actually work (a little) at something. His IQ has allowed him to concentrate for longer periods, read music etc but many in out family are musical so he may have learnt an instrument without the high IQ but we wouldn't have started at 3!
