> Would you assume the same thing about playing a musical instrument or playing a sport?
Yes, of course. Musical ability is well known to be closely associated with mathematical ability. Musical achievement is not known to be closely associated with mathematical achievement; people tend to do one or the other.
But this already tells us that playing an instrument will predict better cognitive performance for reasons unrelated to the work you do to learn the instrument.
I would not assume that playing a sport predicted better cognitive performance, but I obviously would assume that playing a sport intensively predicts better athleticism -- independent of the effect of practicing sports -- than avoiding sports does.
Yes, of course. Musical ability is well known to be closely associated with mathematical ability. Musical achievement is not known to be closely associated with mathematical achievement; people tend to do one or the other.
But this already tells us that playing an instrument will predict better cognitive performance for reasons unrelated to the work you do to learn the instrument.
I would not assume that playing a sport predicted better cognitive performance, but I obviously would assume that playing a sport intensively predicts better athleticism -- independent of the effect of practicing sports -- than avoiding sports does.