Determine about the Brain tissue
Brain tissue looks solid to the naked eye (it has a consistency of stiff jelly), so 'finger-grain' investigations had to await two technological developments. The first was the gradual refinement over many years of the light microscope, and second was the discovery of tissue staining techniques that had the effect of 'highlighting' particular component structures of tissue. The combinations of these developments enable researchers to identify small groups of neurons, or even individual neurons, using a microscope. Thanks to technological improvements in lens manufacture, microscopy has developed considerably since its first reported use to examine biological tissues (of a cow) by Van Leeuwenhoek in1674. Light microscope can now reliably magnify by a factor of several hundred, but electron microscope can magnify by a factor of several thousands. They can produce images of images of individual synapses (junctions between neurons), or even of receptor sites for neurotransmitters on the surface of neurons.