Original sentence: Cajal used a histological staining technique developed by his contemporary Camillo Golgi.Cajal was instrumental in compiling work to support the Neuron doctrine, the idea that neurons are the basic structural and functional units of the nervous system.Golgi found that by treating brain tissue with a silver chromate solution, a relatively small number of cells in the brain were darkly stained.He poetically described neurons in this autobiography as the "mysterious butterflies of the soul".Ramón y Cajal's most famous studies was the discovery of the neuron as we know it.The studies were on the fine structure of the central nervous system.This allowed Cajal to resolve in detail the structure of individual neurons and led him to conclude that nervous tissue was composed of individual, autonomous cells, the neurons, instead of a continuous web
Edited sentence: During this period he made extensive studies of neural material covering a large variety of species and most major regions of the brain.He discovered the axonal growth cone, and provided the best evidence supporting Auguste Forel's theory of nerve cell contact.He provided detailed descriptions of cell types associated with neural structures, and produced excellent depictions of structures and their connectivity.He was a proponent of polarization of nerve cell function and his student Lorente de No would continue this study of input/output systems into cable theory and some of the earliest circuit analysis of neural structures.He was an advocate of the existence of spines, although he did not recognize them as the site of contact from presynaptic cells.It was not until he moved to the University of Barcelona in 1887 that he learned Golgi's silver nitrate preparation and turned his attention to the central nervous system.Ramón y Cajal was a fierce defender of the neuron theory.Ramón y Cajal's early work was accomplished at the Universities of Zagarosa and Valencia where he focused on the pathology of inflammation, the microbiology of cholera, and the structure of epithelial cells and tissues.Ramón y Cajal's made several major contributions to neuroanatomy