I disagree about the IQ. Music has more to do with math than with other artforms.You can't be the next Charlie Parker/John Coltrane with an average IQ. Same with Liszt or Mozart.All elements require brains. Plain mechalical virtuosity requires an unique brain. Creativity, memorisation, etc are clearly intellectual skills.In jazz you have alot to think about and you need to do it really fast, counting, picking the scale, thinging about the chords, recalling which notes you played, what scale and chord combination is next, which notes are vital, how to connect those changes, its endless. Improvisation just requires you to learn alot of musical phrases or 'words'. You need a huge vocabulary.With classical music there is alot of theory to learn. The harmony is subtle, form is important so memory is too, otherwise the form is meaninless, and so is the music. Music is really an intellectual process. More than any other thing I can think of. I personally recovered 15 points of IQ. Music really made me a psuedo-intellectual, reading books on all kinds of sciences and philosophy. I wound have never done that without music.
True, but you said a person with IQ 90 has the same ability as a person with 150. I disagree with that. In general that is not true.