“For simplicity’s sake, they assumed that the brain as a whole could be modeled as a vast, interconnected electrical circuit, with neurons serving as both the wires and the switches. That is, each neuron would receive electrical input from dozens or hundreds of other neurons. And if the total stimulation passed a certain threshold, that neuron would then “fire” and send an output pulse to dozens or hundreds more. The result—today it would be known as a “neural network” model—was admittedly a gross oversimplification of reality.”