science & techanalysisThe Public Domain Review1880s–1906 · Italy and Spain
Golgi and Ramón y Cajal fought over whether neurons touch, and Cajal's answer shaped modern neuroscience
In the late 1880s, Camillo Golgi argued that nerve cells form one continuous network, while Santiago Ramón y Cajal argued they are separate cells that communicate across tiny gaps. Golgi's silver staining method made individual neurons visible for the first time, and Cajal improved it to produce detailed, reliable drawings. Cajal found no evidence of fused networks and proposed that signals pass between neighbouring cells. The two shared the 1906 Nobel Prize, and Golgi used his time on stage to attack Cajal's neuron theory.
Golgi's black reaction soaks tissue in silver nitrate, which deposits dark silver on individual cells and their branches while leaving the rest pale. This made single neurons visible in a way earlier stains had not. Cajal refined the method with thicker sections and young animal tissue, which had less myelin to block the stain. His observations showed that neurons do not fuse, so signals must pass across near contacts.
The neuron doctrine is the foundation of modern neuroscience, and the word synapse was coined later to describe the gap Cajal had proposed. The debate shows how careful staining and drawing can overturn an accepted theory.
Golgi developed his silver staining technique in a makeshift laboratory set up in a hospital kitchen.
background
The neuron doctrine is the concept that the nervous system is made up of discrete individual cells, a discovery due to decisive neuro-anatomical work of Santiago Ramón y Cajal and later presented by, among others, H. Waldeyer-Hartz. The term neuron (spelled neurone in British English) was itself coined by Waldeyer as a way of identifying the cells in question. The neuron doctrine, as it became known, served to position neurons as special cases under the broader cell theory evolved some decades earlier. He appropriated the concept not from his own research but from the disparate observation of the histological work of Albert von Kölliker, Camillo Golgi, Franz Nissl, Santiago Ramón y Cajal, Auguste Forel and others.
From Wikipedia: Neuron doctrine (CC BY-SA 4.0) ↗
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