I know of a few people who are in the Genius level and 3 in particular are virtual hermits. They sleep in the day and live at night, reading or doing what they like. They seem to have become so bored with 'normal' people and life that it is too painful to participate.
So they must be thinking in a way that is beyond the average person to comprehend. I have found for my self that in most cases it is not possible to explain what i see or how i think to most people, they cannot grasp it. Often i cannot explain how i know what i know, i just do.
So as for how the high IQ person thinks, i do not know if that is classifiable because it is in a different and unique method of simply knowing or understanding a thing beyond its surface characteristics.
I have recently posted an article on my site about reincarnation which is a best guess explanation.
I think that there are still the individual characteristics of audio or visual natures of a person for example which rules. I sometimes can 'smell' a good situation or place. Certainly i have a big nose
but i do not have a particularly good sense of smell.
so for me, it is 'smelling' the right place or situation. Otherwise it is a sensation, intuition. and that is what I wrote about in terms of spiritual and normal methodology. It is the first article on the home page now, but new articles are posted twice a week, so you may have to scroll down a bit to see it.