The Fixation of Central Nervous Tissue and the Analysis of Electron Micrographs of the Neuropil, with Special Reference to the Cerebral Cortex

One of the greatest difficulties encountered by electron microscopists studying the central nervous system is the fixation of the tissue. This problem has delayed detailed analyses of the central nervous system in mammals to such an extent that only recently have the descriptions of the individual components of this tissue been completed. By contrast, in other tissues of the body this same stage was arrived at early in the present decade. Even today, a student of the fine structure of the nervous system cannot be certain of obtaining good preservation of his tissue and there are still some parts of the brain and spinal cord that are successfully resisting attempts to study their morphology. These parts are the ones that contain a high proportion of myelinated nerve fibers.