Look at any science discovery/ breakthrough and behind it you will usually find a previous breakthrough in instrumentation or visualization.
A new advanced method developed at the University of Copenhagen
Neurons communicate with each other with the help of nano-sized vesicles. Disruption of this communication process is responsible for many diseases and mental disorders like e.g. depression. Nerve signals travel from one neuron to another through vesicles - a nano-sized container loaded with neurotransmitter molecules. A vesicle fuses with the membrane surrounding a neuron, releases neurotransmitters into the surroundings that are detected by the next neuron in line. However, we still lack a more detailed understanding of how the fusion of vesicles occurs on the nano-scale. We just don't know what happens in the exact pathway(s)...which this method could unravel
see story here Live recordings of cell communication