I came across Guido purely by accident, as I was reading a few things about Vigevano, a town in Northern Italy (where I was born). Guido da Vigevano was a physician and inventor.
Di Ieva, A., Tschabitscher, M., Prada, F., Gaetani, P., Aimar, E., Pisano, P., et al. (2007). The neuroanatomical plates of Guido da Vigevano. Neurosurgical Focus, 23(1), 1-4.
This paper published in 2007 is about his anatomical drawings, which were published in 1345. These are possibly the first accurate drawings of the human brain, which is remarkable. Here is one with some sulci and gyri sort of visible.
Apart from this, Guido also drew what some believe to be the first plan for a car (a cart propelled by a windmill).