Techniques Used On The Nervous System

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Microscopical techniques have been an irreplaceable source of our knowledge about the nervous system. Not only have they provided clear evidence supporting the variety of hypotheses but also deepened our understanding by allowing the researchers to make valid links between the components of the nervous system and their functions. In this paper, I wish to explore the development of these techniques and how they allowed the investigators to arrive to the certain conclusions and dismiss theories created by their predecessors. However, microscopical techniques always had their limitations, which at first impeded scientific research but then turned out to be a unique trigger for innovations. The nature of the adaptations made according to…show more content…
So when examining retinal neurones, there was no certainty if all subclasses of cells were labelled (Morgan et al., 2005). Vittorio Marchi was a pioneer of degeneration techniques. At first, the myelin sheath degeneration technique suggested by him was considered to have an enormous potential, but as the method involved staining breakdown products of myelin, some pathways were not stained, especially if they were not myelinated well enough. In 1913, Nissil stated that soma of the neurons in the principal nuclei of the thalamus degenerate if the cortex is damaged. He used dyes such as cresyl violet and methylene blue, which revealed the changes occurring in soma of the cell with damaged axons (Cowan, 1998). This technique was very useful for mapping distribution, but not for distinguishing the stained cells, since the soma size of some cells (e.g. in retina) is almost the same (Morgan et al., 2005). A solution was found in 1962 when Falck described methods to determine amines produced in tissue sections, which enabled mapping neuron classes based on the neurotransmitter used (Cowan, 1998). Since then this method has been improved by applying vast range antibodies against the whole variety of neuroproteins (Wouterlood and Lohman, 1991). The autoradiographic technique using a radioactive hydrogen isotope proposed by Taylor and Weiss in 1965 solved the problems associated with the degeneration methods as
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