[The neuroanatomy of Juan Valverde de Amusco and medicine at the time of the Spanish renaissance].

Juan Valverde de Amusco (c. 1525-c. 1564) is considered to have been the most important Spanish anatomist of the XVI century. A follower of Vesalius, he increased and divulged knowledge of anatomy during the Renaissance and his book The history of the composition of the human body was printed in Rome in 1556. The objective of this paper is to study the neuroanatomy in this book and present unpublished biographical data and describe the main contributions of this Castilian doctor to the neurosciences, in the context of Spanish medicine during the Renaissance period. He was born in the town of Hamusco (today Amusco) in the province of Palencia, which belonged to the Crown of Castile. Juan Valverde emigrated to Italy to improve his scientific knowledge. He carried out anatomical studies using the then revolutionary method of direct observation, as opposed to the Galenic criteria of authority inherited from the Medieval period. He trained in Padua under Realdo Colombo and lived in Rome where he practiced medicine until his death, becoming deservedly famous. He did not return to Spain since in the Spanish universities of the time there was a mentality which was reactionary to modern anatomy. His works, published in Italy but in the Spanish language, give an idea of the power of the Crown of Castile in the Europe of that period. The book is profusely illustrated with the first illustrations ever published in the history of printing, drawn by Nicolas Beatrizet. The book was sold widely and was translated and reedited on many occasions, until well into the XVIII century. For the first time Valverde made precise references to the minor circulation. He was the first anatomist to describe the muscles for movement of the eye correctly and the intracranial course of the carotid arteries. In his work he made the first drawing of the stapes, described by the Valencian Luis Collado. Vesalius and Valverde contributed decisively to the beginnings of modern neuroanatomy. Thanks to them, the brain is no longer an organ unknown to science.