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brain-region graphically :
In the first half of the 19th century, Jean Pierre Flourens pioneered the experimental method of carrying out localized lesions of the brain in living animals describing their effects on motricity, sensibility and behaviour. In 1843 Emil du Bois-Reymond demonstrated the electrical nature of the nerve signal, whose speed von Helmholtz proceeded to measure. In 1875 Richard Caton found electrical phenomena in the cerebral hemispheres of rabbits and monkeys. Adolf Beck published in 1890 similar observations of spontaneous electrical activity of the brain of rabbits and dogs. Studies of the brain became more sophisticated after the invention of the microscope & development of a staining procedure by Camillo Golgi during the late 1890s, which revealed the intricate structures of individual neurons. This technique led to the formation of the neuron doctrine, the hypothesis that the functional unit of the brain is the neuron. Golgi & Ramón y Cajal shared the Nobel Prize in Physiology (1906) for their descriptions & categorizations of neurons throughout the brain.
