One of the first research projects that I was involved in some 12-13 years ago
was a correlation study of MRI structures, grey/white ratios, etc. to
intellegence and personality profiles. The PI at the time was Lee Willerman. I
don't know where or how it was published, but I remember that various
relationships did show up. I may be wrong, you'll have to look it up, but I
think the best relationships to intellegence were in the temporal lobes.