This is a new book by Dr. Davson and not just a new edition of his old book, Physiology of Ocular and Cerebrospinal Fluids. It includes a consideration of the extracellular fluid of the brain and the problem of the blood-brain barriers as well as the physiology of the cerebrospinal fluid.
Dr. Davson brings together much of the new experimental work that has been done in the last 15 years. He demonstrates that both the cerebrospinal fluid (CSF) and the extracellular fluid of the brain are secretions in the sense that they are the products of metabolic effort. He points out that this conclusion means a controlled production of extracellular fluid in the central nervous system as contrasted to simple filtration, which takes place in other tissues. He suggests that the extracellular fluid does indeed drain from the brain into the CSF, and he relates the amount produced to the