The ventricles in one of Leonardo DaVinci’s anatomical drawings are huge and a different form than human ventricles. He was an extraordinary artist. Why did he draw them out of scale? This question led me to explore the ventricles from an historical perspective. The following is a brief account.
- Systemic human dissection began in the Hellenistic Era (323-30BC). Herophilus of Chalcedon practiced as a physician around 300BC and he preformed hundreds of dissections. He proposed that the fourth ventricle housed the soul.
- Galen of Pergamon (129-216AD) was a physician, physiologist, philosopher, and writer who is often considered the most important contributor to medicine following Hippocrates. He suggested that animal spirits are produced in the choroid plexuses of the ventricles, and that these spirits act as the physical manifestation of the soul.
- Around 400AD, Nemesius, Bishop of Emesa (which was in Syria), blended the medical science of Galen with Christian theology and stated that the ventricles are the home of the soul and that each ventricle has a specific function. He related perception to the two lateral ventricles, cognition to the third, and memory to the fourth. Scholarly Christians supported this view throughout the Dark Ages (476-1000AD).
- Leonardo DaVinci (1452-1519AD), painter, sculptor, architect, scientist and master of other disciplines, proposed that the ventricles are the home of the soul, sensation, cognition and memory. DaVinci used oxen for some of his ventricle research. One method he used was to insert a tube into opposite ends of the ventricles. He poured melted wax into one tube, and as this wax flowed into the ventricles it displaced cerebrospinal fluid, which drained out of the other tube. When the wax cooled he dissected the form out of the brain and in doing so had a replica of the oxen ventricles. In one of his anatomical drawings he drew the oxen ventricular form within a human brain.
- Rene Descartes (1596-1650AD) was a philosopher who used geometry, physics and mechanical models to explain his ideas. He thought that tiny particles from the blood filtered into the pineal gland and the pineal converted these particles into animal spirits. These spirits were then released by the pineal gland into the ventricles. The pineal would mechanically pull on the ventricular walls to direct the flow of these spirits into the nerves allowing them to flow into the body. He also believed that it was through the pineal gland that the soul became aware of the flow of animal spirits, which allowed the soul to perceive, imagine and generate new ideas.
- Thomas Willis (1621-1675AD) was a physician and brilliant researcher. He proposed that only humans possess an immortal soul, and it cannot be studied anatomically or physiologically since it is intangible. On the other hand perception, cognition and memory, which he called the corporeal (physical) soul, can be linked to the brain and consequently can be studied scientifically. He proposed that the brain tissue itself was the site of the physical soul, not the ventricles.
- William G. Sutherland, D.O. (1873-1954AD), the creator of Cranial Osteopathy, believed that a divine spirit enters the ventricles. He called this spirit the “breath of life” and it is carried by cerebrospinal fluid to the entire body. Thus the breath of life is manifested in the anatomy and physiology of each cell and the body as a whole. Dr. Sutherland hypothesized that the breath of life merges with brain pulsations to create the craniosacral rhythm.
- John E. Upledger, D.O., O.M.M., (1932- present) the founder of CranioSacral Therapy, proposed that the ventricles mechanically create the craniosacral rhythm. He suggests that the ventricles produce cerebrospinal fluid in on-and-off phases. These phases create an increase and decrease of cerebrospinal fluid pressure within the container of the brain and spinal cord. The fluid pressure changes are then felt as the craniosacral rhythm.
The ventricles are cavities deep within the brain, birdlike in form with wings, body and tail located within major portions of the brain.