History of Neurology - Microscopy

Microscopy

Only when cells were identified microscopically was it possible to progress beyond the crudest anatomical notion. J.E. Purkinje (1787–1869) in 1837 gave the first description of neurones, indeed a very early description of cells of any kind. Later Golgi and Cajal stained the ramifying branches of nerve cells; these could only touch, or synapse. The brain now had demonstrated form, without localised function. The famous philosopher René Descartes (1596–1650) speculated that every activity of an animal was a necessary reaction to some external stimulus; the connection between the stimulus and the response was made through a definite nervous path. Luigi Galvani (1737–1798) demonstrated that electrical stimulation of nerve produced muscle contraction, and the competing work of Charles Bell (1774–1842) and Francois Magendie (1783–1855 ) led to the view that the ventral horns of the spinal cord were motor and the dorsal horns sensory. A hemiplegic patient who could not speak led Paul Broca (1824–1880) to the view that functions in the cerebral cortex were anatomically localised. Ivan Pavlov (1849–1936) realised as his dogs dribbled that a simple reflex could be modified by higher brain functions. These neurological ideas were coordinated and integrated by the neurophysiologist Charles Scott Sherrington (1857–1952).