form this post on reddit, which i thought was very interesting
Assuming that these findings are correct, and that the likeness between Michelangelos painting and human anatomy, particularly the brain and brain-stem, What do you think he meant by it? Do you think it means that god was endowing Adam with consciousness or that the "brain" that exists in is makes us in a sense gods?
Or him having a tongue-in-cheek dig at the Church going "*It's all in your head*". There's a good analysis of Michelangelo's work and a couple others as well. Rafael's seems to be a bit of a stretch, but David's Transfiguration bears a good resemblance to a cross section of the brain too. Still, The Creation of Adam is most definitely a brain in disguise, I am in awe at Michelangelo's ability to craft it without the holier-than-thous really realising.
as it is mentioned in the thread "and on the sixth day man created god in his own image" also worth mentioning is that gods arm comes out of the frontal lobe, or "third eye" which could be something about the divine in creation of things, wether that be paintings or music etc.