From The Guardian:
“Any onlooker fleetingly imagining they spotted a human brain in the flurry of cherubs and drapery swirling around the figure of God as he stretches out a hand to raise Adam to life in Michelangelo’s famous fresco from the Sistine Chapel would probably conclude there was some malfunction in their own brain.
However, four eminent scientists are convinced the swirls are not meaningless decoration, but a transverse section of the sagittal section of a human brain.
The resemblance to a brain was first suggested by another scientist, FL Meshberger, but now Alessandro Paluzzi, Antonio Belli, Peter Bain and Laura Viva, from the neurosurgery, neurosciences and radiology departments of James Cook university hospital in Middlesbrough, Teesside, Charing Cross hospital in London and Southampton University, have dissected his theory and tracked down more brains in masterpieces by other Renaissance painters. "The idea came to me while looking at Raffaello’s Transfiguration. Being a neurosurgeon I could immediately see a brain in the painting," Paluzzi said.
Partly as a joke to entertain sceptical colleagues, he and the team went on a brain trawl, and found many other examples. The team is convinced the artists were fascinated by the scientific discoveries being made by anatomists, but their theories had to be concealed in the imagery of their paintings, particularly when their clients were so often senior clergy who might see their scientific interests as blasphemous or even heretical, an offence punishable by death. The study, Brain imaging in the Renaissance, features in the Journal of the Royal Society of Medicine.