Neuropsychology: The Cell Doctrine

This theory postulated that mental and spiritual processes/functions were localized in the ventricles (called Cells) of the brain. The theory was proposed by Nemesius and Saint Augustine in approximatley 130-200 A.D. It was strongly influenced by the anatomical studies of Galen in the second century, in which he described the ventricles in detail and developed his own theory of "psychic gases and humours", that flowed through the body and ventricles (thus, the "ventricular localization hypothesis"), giving rise to mental functions. (He also characterized the brain as a "large clot of phlegm".) The idea that the veltricles were merely a sewer system through which passed bodily fluids, led to the theory of the importance of "humors" which has persisted for 1000 years. Mental functions derived from the descriptions of Aristotle, such as memory, attention, fantasy and reason, were assigned locations within the ventricles. These images depict the connections between the senses (vision, hearing etc.) and the "Common Sense", located in the first ventricle. Cognitive functions were then arrayed from front to back in the ventricles. This Doctrine was proven to be totally false, as we now know that the ventricles are the site through which cerebrospinal fluid passes.
From this period, many important discoveries and theories were noted. Dissections of condemned criminals (who, at that time, were at the disposal of scientists and physicians) led to the knowledge that specific parts of the brain control specific behaviors (discussed later as localization). As well, the discovery of ascending (sensory) and descending (motor) nerves occurred. Galen (circa 200 BC), a prominent ancient Greek physician, performed many operations, including brain and eye surgeries, and also “vivisections” of numerous animals to study the function of the kidneys and the spinal cord. Galen hypothesized that the mind controlled fluids known as pneuma (animal spirits): the brain was the reservoir of pneuma, which were stored in the ventricles. Pneuma traveled through nerves, which Galen believed were tubes, throughout the body - sent out from the brain to the muscles (i.e., controlled by the mind, causing the body to move) and sent back to the brain due to sensory stimulation. Physical functioning was dictated by the balance of four bodily fluids or humors: Blood, Mucus, Yellow bile, Black bile, which were related to the four elements - air, water, fire, and earth. Galen also showed that pressing on the heart in human subjects did not lead to loss of consciousness or loss of sensation but severing the spinal cord in animals abolished sensory responses after brain stimulation.