Looking some more at the brain, and creativity.
I came across this video about the artist, Alison Silva, in which we learn that she has a strange clotting up of blood vessels in her brain, and her concerns that if/when she has an operation to deal with this, she will lose her ability to be creative.
Since the clotting made its appearance, her art has taken a different tone and colouring.
Watch CBS Videos Online
Thanks to Jurgen Wolff for alerting me to this video. (But why oh why do news reporters talk in such a condescending way?)