One of the curious properties of brain activity — the firing of neurons — is that it follows certain patterns. One of these is that brain activity tends to be maintained rather than dampened or amplified.
This turns out to be a special phenomenon of self-organization. Active neurons tend to trigger other neurons. If each active neuron triggers more than one other, any activity is rapidly amplified in a chain reaction. If each neuron triggers less than one other, the activity tends to fizzle out, like a damp firework.
But to maintain activity, each active neuron must trigger about one other neuron. Neuroscientists call this criticality and believe that it maximizes the flow of information through a neural network.
