Part Two of The Renaissance Brain Mini-Series.
Part One can be found here: http://www.examiner.com/science-news-in-allentown/cerebrum-renatus-the-renaissance-brain-i
Leonardo da Vinci, the true Renaissance man, developed the idea of sketching to allow for fluid embodiment of his brainstorming and rapid ideas (Kickhöfel, 2009). His idea of the sketch served him well, especially with his work in anatomical renditions, including those of the brain. His motto in anaomtical study was sapere vedere, or ‘know how to see’. In the early 1500’s, da Vinci worked to understand the anatomy of the brain’s ventricles. He injected cattle brains with molten wax by using a syringe in order to decipher the true ventricular delineations of the brain (Finger, 1994). He used his wax casts to then create artistic renditions of the ventricles and to further knowledge of the brain’s true shape. This is the first known occasion in which a coagulating substance was used in an effort to ascertain the form of an internal structure (Pevsner, 2002). Da vinci’s drawings of the skull included the first accurate depictions of the middle and anterior meningeal arteries, and the cranial fossae (Pevsner, 2002). Some of his skull drawings identify the frontal sinus, which was an original discovery on da Vinci’s part. His skull drawings also show the center of gravity upon which the body of the head rotates (Pevsner, 2002). Leonardo da Vinci was the first scientist to pith animals. He reckoned that the spinal cord was the control region for movement and was the source of sustenance of life. Based on his experimental evidence, he determined that the spinal cord was necessary not only for movement and life, but also for tactile sensation and was the region of origin for the nerves enervating the limbs (Pevsner, 2002). However, he also believed that the soul residing in the brain could generate movement. Even through these ingenious endeavors, the prevailing thought of the time, also accepted by da Vinci, was that a spirit moved through the nerves and into the ventricles, and vice versa, and controlled the outpourings of the brain, including sensory information, cognition, and movement. The prevailing idea of his time was that the soul was thought to have origin in the head of person, but was seated within the ventricles, since the soul is a disembodied aspect of humans and would not reside in the tissue of the brain itself. Leonardo da Vinci worked, like other contemporary scientists, to discover the seat of the soul, which he and others believed was within the brain’s ventricles. Leonard’s skull drawings depict the third ventricle, which was considered the area of common sense, the region at which the sense converge (senso commune), and which was believed to be the seat of the soul (Pevsner, 2002). However, even with his spiritual view of the brain’s ventricular system, da Vinci described it using mechanical terminology, including force and pressure (Pevsner, 2002). Leonardo da vinci’s work, however, remained unknown until the 1800’s, when Andreas Vesalius expanded knowledge of the ventricular system (Greenblatt, 1997).
Finger, Stanley. Origins of Neuroscience: A History of Explorations into Brain Functions. New York, USA: Oxford University Press: 1994.
Greenblatt, Samuel H. A History of Neurosurgery in its Scientific and Professional Contexts. Illinois, USA: The American Association of Neurological Surgeons: 1997.
Kickhöfel, Eduardo H.P., (2009) Sine ars scientia nihil est: Leonardo da Vinci and beyond. Epilepsy and Behavior, 14, 5-11.
Pevsner, Jonathan (2002). Leonardo da Vinci’ contributions to Neuroscience. TRENDS in Neuroscience, 25, 217-220.
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